diff --git a/man/mu-index.1 b/man/mu-index.1
index cc1e45e1..1a00bfb6 100644
--- a/man/mu-index.1
+++ b/man/mu-index.1
@@ -90,18 +90,22 @@ set the maximum number of messages to process in a single Xapian
 transaction. In practice, this option is only useful if you find that \fBmu\fR
 is running out of memory while indexing; in that case, you can set the batch
 size to (for example) 1000, which will reduce memory consumption, but also
-reduce performance.
+substantially reduce the indexing performance.
+
+.TP
+\fB\-\-max-msg-size\fR=\fI<max msg size>\fR
+set the maximum size (in bytes) for messages. The default maximum (currently
+at 50Mb) should be enough in most cases, but if you encounter warnings from
+\fBmu\fR about ignoring messsage because they are too big, you may want to
+increase this. Note that the reason for having a maximum size is that big
+message require big memory allocations, which may lead to problems.
 
 .B NOTE:
-It is generally not a good idea to run multiple instances of \fBmu index\fR
-concurrently. No data loss should occur, but one or more of the instances may
-experience errors due to database locks.
-
-Furthermore, it is not recommended tot mix maildirs and sub-maildirs within
-the hierarchy in the same database; for example, it's better not to index both
-with \fB\-\-maildir\fR=~/MyMaildir and \fB\-\-maildir\fR=~/MyMaildir/foo, as
-this may lead to unexpected results when searching with the the 'maildir:'
-search parameter (see below).
+It is not recommended tot mix maildirs and sub-maildirs within the hierarchy
+in the same database; for example, it's better not to index both with
+\fB\-\-maildir\fR=~/MyMaildir and \fB\-\-maildir\fR=~/MyMaildir/foo, as this
+may lead to unexpected results when searching with the the 'maildir:' search
+parameter (see below).
 
 .SS A note on performance
 As a non-scientific benchmark, a simple test on the authors machine (a
diff --git a/src/mu-cmd-index.c b/src/mu-cmd-index.c
index 4c2d9496..99c2dff3 100644
--- a/src/mu-cmd-index.c
+++ b/src/mu-cmd-index.c
@@ -94,7 +94,12 @@ check_index_or_cleanup_params (MuConfig *opts)
 		g_warning ("the Xapian batch size must be non-negative");
 		return FALSE;
 	}
-		
+
+	if (opts->max_msg_size < 0) {
+		g_warning ("the maximum message size must be non-negative");
+		return FALSE;
+	}
+	
 	return TRUE;
 }
 
@@ -346,10 +351,12 @@ cmd_index_or_cleanup (MuConfig *opts)
 		return MU_EXITCODE_ERROR;		
 	
 	err = NULL;
-	if (!(midx = mu_index_new
-	      (mu_runtime_xapian_dir(), opts->xbatchsize, &err)))
+	if (!(midx = mu_index_new (mu_runtime_xapian_dir(), &err)))
 		return handle_index_error_and_free (err);
-
+	
+	mu_index_set_max_msg_size (midx, opts->max_msg_size); 
+	mu_index_set_xbatch_size (midx, opts->xbatchsize);
+	
 	/* we determine the maildir path only here, as it may depend on
          * mu_index_last_used_maildir
          */
diff --git a/src/mu-config.c b/src/mu-config.c
index 661b947d..96d20b8a 100644
--- a/src/mu-config.c
+++ b/src/mu-config.c
@@ -96,6 +96,8 @@ config_options_group_index (MuConfig * opts)
 				 "don't clean up the database after indexing (false)", NULL},
 				{"xbatchsize", 0, 0, G_OPTION_ARG_INT, &opts->xbatchsize,
 				 "set transaction batchsize for xapian commits (0)", NULL},
+				{"max-msg-size", 0, 0, G_OPTION_ARG_INT, &opts->max_msg_size,
+				 "set the maximum size for message files", NULL},
 				{NULL, 0, 0, 0, NULL, NULL, NULL}
 		};
 
diff --git a/src/mu-config.h b/src/mu-config.h
index 3d6c1cff..0d7d17dc 100644
--- a/src/mu-config.h
+++ b/src/mu-config.h
@@ -72,9 +72,10 @@ struct _MuConfig {
 		gboolean         rebuild;		/* empty the database before indexing */
 		gboolean         autoupgrade;   /* automatically upgrade db
 										 * when needed */
-		int				 xbatchsize;    /* batchsize for xapian
+		int              xbatchsize;    /* batchsize for xapian
 										 * commits, or 0 for
 										 * default */
+		int			     max_msg_size;  /* maximum size for message files */
 	
 		/* options for querying */
 		gboolean         xquery;        /* (obsolete) give the Xapian
diff --git a/src/mu-index.c b/src/mu-index.c
index a93b1a98..34e3562e 100644
--- a/src/mu-index.c
+++ b/src/mu-index.c
@@ -35,16 +35,17 @@
 #include "mu-util.h"
 
 #define	MU_LAST_USED_MAILDIR_KEY "last_used_maildir"
-#define MU_MAILDIR_WALK_MAX_FILE_SIZE (64*1000*1000)
+#define MU_INDEX_MAX_FILE_SIZE (50*1000*1000) /* 50 Mb */
 
 struct _MuIndex {
 	MuStore		*_store;
 	gboolean	 _needs_reindex;
 	gchar           *_last_used_maildir;
+	guint            _max_filesize;
 };
 
 MuIndex* 
-mu_index_new (const char *xpath, guint xbatchsize, GError **err)
+mu_index_new (const char *xpath, GError **err)
 {
 	MuIndex *index;
 
@@ -52,7 +53,7 @@ mu_index_new (const char *xpath, guint xbatchsize, GError **err)
 	
 	index = g_new0 (MuIndex, 1);				
 
-	index->_store = mu_store_new (xpath, xbatchsize, err);	
+	index->_store = mu_store_new (xpath, err);	
 	if (!index->_store) {
 		g_warning ("%s: failed to open xapian store (%s)",
 			   __FUNCTION__, xpath); 
@@ -60,6 +61,9 @@ mu_index_new (const char *xpath, guint xbatchsize, GError **err)
 		return NULL;
 	}
 
+	/* set the default max file size */
+	index->_max_filesize = MU_INDEX_MAX_FILE_SIZE;
+	
 	/* see we need to reindex the database; note, there is a small
 	 * race-condition here, between mu_index_new and
 	 * mu_index_run. Maybe do the check in mu_index_run
@@ -73,7 +77,6 @@ mu_index_new (const char *xpath, guint xbatchsize, GError **err)
 	return index;
 }
 
-
 void 
 mu_index_destroy (MuIndex *index)
 {
@@ -88,13 +91,14 @@ mu_index_destroy (MuIndex *index)
 
 
 struct _MuIndexCallbackData {
-	MuIndexMsgCallback		_idx_msg_cb;
-	MuIndexDirCallback		_idx_dir_cb;
-	MuStore*			_store;
-	void*				_user_data;
-	MuIndexStats*			_stats;
-	gboolean			_reindex;
-	time_t				_dirstamp;
+	MuIndexMsgCallback	_idx_msg_cb;
+	MuIndexDirCallback	_idx_dir_cb;
+	MuStore*		_store;
+	void*			_user_data;
+	MuIndexStats*		_stats;
+	gboolean		_reindex;
+	time_t			_dirstamp;
+	guint			_max_filesize;
 };
 typedef struct _MuIndexCallbackData	MuIndexCallbackData;
 
@@ -181,9 +185,9 @@ on_run_maildir_msg (const char* fullpath, const char* mdir,
 	gboolean updated;
 
 	/* protect against too big messages */
-	if (G_UNLIKELY(statbuf->st_size > MU_MAILDIR_WALK_MAX_FILE_SIZE)) {
-		g_warning ("ignoring because bigger than %d bytes: %s",
-			   MU_MAILDIR_WALK_MAX_FILE_SIZE, fullpath);
+	if (G_UNLIKELY(statbuf->st_size > data->_max_filesize)) {
+		g_warning ("ignoring because bigger than %u bytes: %s",
+			   data->_max_filesize, fullpath);
 		return MU_OK; /* not an error */
 	}
 	
@@ -200,10 +204,6 @@ on_run_maildir_msg (const char* fullpath, const char* mdir,
 	if (result == MU_OK && data && data->_stats) { 	/* update statistics */
 		++data->_stats->_processed;
 		updated ? ++data->_stats->_updated : ++data->_stats->_uptodate;
-		/* if (updated)  */
-		/* 	++data->_stats->_updated; */
-		/* else */
-		/* 	++data->_stats->_uptodate; */
 	}
 
 	return result;
@@ -260,7 +260,7 @@ check_path (const char* path)
 
 static void
 init_cb_data (MuIndexCallbackData *cb_data, MuStore  *xapian,
-	      gboolean reindex, MuIndexStats *stats,
+	      gboolean reindex, guint max_filesize, MuIndexStats *stats,
 	      MuIndexMsgCallback msg_cb, MuIndexDirCallback dir_cb, 
 	      void *user_data)
 {
@@ -268,11 +268,12 @@ init_cb_data (MuIndexCallbackData *cb_data, MuStore  *xapian,
 	cb_data->_idx_dir_cb    = dir_cb;
 	
 	cb_data->_user_data     = user_data;
-	cb_data->_store        = xapian;
+	cb_data->_store         = xapian;
 			         
 	cb_data->_reindex       = reindex;
 	cb_data->_dirstamp      = 0;	
-
+	cb_data->_max_filesize  = max_filesize;
+	
 	cb_data->_stats         = stats;
 	if (cb_data->_stats)
 		memset (cb_data->_stats, 0, sizeof(MuIndexStats));
@@ -298,6 +299,26 @@ mu_index_last_used_maildir (MuIndex *index)
 				       MU_LAST_USED_MAILDIR_KEY);
 }
 
+void
+mu_index_set_max_msg_size (MuIndex *index, guint max_size)
+{
+	g_return_if_fail (index);
+
+	if (max_size == 0)
+		index->_max_filesize = 	MU_INDEX_MAX_FILE_SIZE;
+	else
+		index->_max_filesize = max_size;
+}
+
+void
+mu_index_set_xbatch_size (MuIndex *index, guint xbatchsize)
+{
+	g_return_if_fail (index);
+	mu_store_set_batch_size (index->_store, xbatchsize);
+}
+
+
+
 
 MuResult
 mu_index_run (MuIndex *index, const char* path,
@@ -319,7 +340,8 @@ mu_index_run (MuIndex *index, const char* path,
 		return MU_ERROR;
 	}
 	
-	init_cb_data (&cb_data, index->_store, reindex, stats,
+	init_cb_data (&cb_data, index->_store, reindex,
+		      index->_max_filesize, stats,
 		      msg_cb, dir_cb, user_data);
 
 	update_last_used_maildir (index, path);
@@ -400,15 +422,11 @@ typedef struct _CleanupData CleanupData;
 static MuResult
 foreach_doc_cb (const char* path, CleanupData *cudata)
 {
-	MuResult rv;
-	
 	if (access (path, R_OK) != 0) {
-		
-		g_debug ("not readable: %s; removing", path);
-		rv = mu_store_remove (cudata->_store, path);
-		if (rv != MU_OK)
-			return rv; /* something went wrong... bail out */	
-		
+		if (errno != EACCES)
+			g_warning ("cannot access %s: %s", path, strerror(errno));
+		if (!mu_store_remove (cudata->_store, path))
+			return MU_ERROR; /* something went wrong... bail out */
 		if (cudata->_stats)
 			++cudata->_stats->_cleaned_up;
 	}
diff --git a/src/mu-index.h b/src/mu-index.h
index 1d50f076..c0c090ef 100644
--- a/src/mu-index.h
+++ b/src/mu-index.h
@@ -46,13 +46,12 @@ typedef struct _MuIndexStats MuIndexStats;
  *
  * @param xpath path to the 'homedir'; the xapian directory will be
  * this homedir/xapian
- * @param batchsize for Xapian queries, or 0 for the default
  * @param err to receive error or NULL; there are only errors when this
  * function returns NULL. Possible errors: see mu-error.h
  * 
  * @return a new MuIndex instance, or NULL in case of error
  */
-MuIndex* mu_index_new (const char* muhome, guint batchsize, GError **err)
+MuIndex* mu_index_new (const char* muhome, GError **err)
     G_GNUC_MALLOC G_GNUC_WARN_UNUSED_RESULT;
 
 
@@ -64,6 +63,28 @@ MuIndex* mu_index_new (const char* muhome, guint batchsize, GError **err)
 void mu_index_destroy (MuIndex *index);
 
 
+/**
+ * change the maximum file size that mu-index considers from its
+ * default (MU_INDEX_MAX_FILE_SIZE). Note that the maximum size is a
+ * protection against mu (or the libraries it uses) allocating too
+ * much memory, which can lead to problems
+ * 
+ * @param index a mu index object
+ * @param max_size the maximum msg size, or 0 to reset to the default
+ */
+void mu_index_set_max_msg_size (MuIndex *index, guint max_size);
+
+
+/**
+ * change batch size for Xapian store transaction (see
+ * 'mu_store_set_batch_size')
+ * 
+ * @param index a mu index object
+ * @param max_size the batch size, or 0 to reset to the default
+ */
+void mu_index_set_xbatch_size (MuIndex *index, guint xbatchsize);
+
+
 /**
  * get the maildir for the last run of indexing for the
  * current database
diff --git a/src/mu-store.cc b/src/mu-store.cc
index 4cda56b1..ed0056e4 100644
--- a/src/mu-store.cc
+++ b/src/mu-store.cc
@@ -1,5 +1,5 @@
 /*
-** Copyright (C) 2008-2010 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
+** Copyright (C) 2008-2011 Dirk-Jan C. Binnema <djcb@djcbsoftware.nl>
 **
 ** This program is free software; you can redistribute it and/or modify it
 ** under the terms of the GNU General Public License as published by the
@@ -119,7 +119,7 @@ check_version (MuStore *store)
 }
 
 MuStore*
-mu_store_new  (const char* xpath, guint batchsize, GError **err)
+mu_store_new  (const char* xpath, GError **err)
 {
 	MuStore *store (0);
 	
@@ -139,7 +139,7 @@ mu_store_new  (const char* xpath, guint batchsize, GError **err)
 		/* keep count of processed docs */
 		store->_in_transaction = false;
 		store->_processed      = 0;
-		store->_trx_size       = batchsize ? batchsize : MU_STORE_DEFAULT_TRX_SIZE;
+		store->_trx_size       = MU_STORE_DEFAULT_TRX_SIZE;
 		
 		add_synonyms (store);
 		
@@ -177,6 +177,18 @@ mu_store_destroy (MuStore *store)
 }
 
 
+void
+mu_store_set_batch_size (MuStore *store, guint batchsize)
+{
+	g_return_if_fail (store);
+	
+	if (batchsize == 0)
+		store->_trx_size = MU_STORE_DEFAULT_TRX_SIZE;
+	else
+		store->_trx_size = batchsize;
+}
+
+
 
 unsigned
 mu_store_count (MuStore *store)
@@ -521,11 +533,11 @@ mu_store_store (MuStore *store, MuMsg *msg)
 }
 
 
-MuResult
-mu_store_remove (MuStore *store, const char* msgpath)
+gboolean
+mu_store_remove (MuStore *store, const char *msgpath)
 {
-	g_return_val_if_fail (store, MU_ERROR);
-	g_return_val_if_fail (msgpath, MU_ERROR);
+	g_return_val_if_fail (store, FALSE);
+	g_return_val_if_fail (msgpath, FALSE);
 
 	try {
 		const std::string uid (get_message_uid (msgpath));
@@ -533,18 +545,15 @@ mu_store_remove (MuStore *store, const char* msgpath)
 		begin_trx_if (store, !store->_in_transaction);
 		
 		store->_db->delete_document (uid);
-		g_debug ("deleting %s", msgpath);
-		
 		++store->_processed;
 
 		/* do we need to commit now? */
 		bool commit_now = store->_processed % store->_trx_size == 0;
 		commit_trx_if (store, commit_now);
 
-		return MU_OK; 
+		return TRUE; 
 		
-	} MU_XAPIAN_CATCH_BLOCK_RETURN (MU_ERROR);
-	
+	} MU_XAPIAN_CATCH_BLOCK_RETURN (FALSE);	
 }
 
 gboolean
diff --git a/src/mu-store.h b/src/mu-store.h
index 78a8069b..53069b30 100644
--- a/src/mu-store.h
+++ b/src/mu-store.h
@@ -41,7 +41,7 @@ typedef struct _MuStore MuStore;
  * 
  * @return a new MuStore object, or NULL in case of error
  */
-MuStore*    mu_store_new     (const char *path, guint batchsize, GError **err)
+MuStore*    mu_store_new     (const char *path,  GError **err)
     G_GNUC_MALLOC G_GNUC_WARN_UNUSED_RESULT;
 
 
@@ -53,6 +53,20 @@ MuStore*    mu_store_new     (const char *path, guint batchsize, GError **err)
 void        mu_store_destroy (MuStore *store);
 
 
+
+/**
+ * set the Xapian batch size for this store. Normally, there's no need
+ * to use this function as the default is good enough; however, if you
+ * use mu in a very memory-constrained environment, you can set the
+ * batchsize to e.g. 1000 at the cost of significant slow-down.
+ * 
+ * @param store a valid store object
+ * @param batchsize the new batch size; or 0 to reset to
+ * the default batch size
+ */
+void  mu_store_set_batch_size (MuStore *store, guint batchsize);
+
+
 /**
  * get the numbers of documents in the database
  * 
@@ -104,8 +118,7 @@ MuResult mu_store_store   (MuStore *store, MuMsg *msg);
  * 
  * @return TRUE if it succeeded, FALSE otherwise
  */
-MuResult mu_store_remove (MuStore *store,
-			  const char* msgpath);
+gboolean mu_store_remove (MuStore *store, const char* msgpath);
 
 
 /**
@@ -114,10 +127,9 @@ MuResult mu_store_remove (MuStore *store,
  * @param store a store
  * @param path the message path
  * 
- * @return 
+ * @return TRUE if the message exists, FALSE otherwise
  */
-gboolean mu_store_contains_message (MuStore *store,
-				    const char* path);
+gboolean mu_store_contains_message (MuStore *store,  const char* path);
 
 /**
  * store a timestamp for a directory
diff --git a/src/tests/test-mu-cmd.c b/src/tests/test-mu-cmd.c
index 237d9ec8..80cf45e1 100644
--- a/src/tests/test-mu-cmd.c
+++ b/src/tests/test-mu-cmd.c
@@ -110,7 +110,7 @@ test_mu_index (void)
 
 		xpath = g_strdup_printf ("%s%c%s", muhome, G_DIR_SEPARATOR, "xapian");
 	
-		store = mu_store_new (xpath, 0, NULL);
+		store = mu_store_new (xpath, NULL);
 		g_assert (store);
 
 		g_assert_cmpuint (mu_store_count (store), ==, 5);	
diff --git a/src/tests/test-mu-store.c b/src/tests/test-mu-store.c
index 0511f65e..4329dae9 100644
--- a/src/tests/test-mu-store.c
+++ b/src/tests/test-mu-store.c
@@ -42,7 +42,7 @@ test_mu_store_new_destroy (void)
 		g_assert (tmpdir);
 
 		err = NULL;
-		store = mu_store_new (tmpdir, 12345, &err);	
+		store = mu_store_new (tmpdir, &err);	
 		g_assert (store);
 		g_assert (err == NULL);
 
@@ -67,7 +67,7 @@ test_mu_store_version (void)
 		g_assert (tmpdir);
 
 		err = NULL;
-		store = mu_store_new (tmpdir, 789, &err);	
+		store = mu_store_new (tmpdir, &err);	
 		g_assert (store);
 		g_assert (err == NULL);
 
@@ -90,7 +90,7 @@ test_mu_store_store_and_count (void)
 		tmpdir = test_mu_common_get_random_tmpdir();
 		g_assert (tmpdir);
 
-		store = mu_store_new (tmpdir, 1, NULL);	
+		store = mu_store_new (tmpdir, NULL);	
 		g_assert (store);
 		
 		g_assert_cmpuint (0,==,mu_store_count (store));
@@ -138,7 +138,7 @@ test_mu_store_store_remove_and_count (void)
 		tmpdir = test_mu_common_get_random_tmpdir();
 		g_assert (tmpdir);
 
-		store = mu_store_new (tmpdir, 0, NULL);	
+		store = mu_store_new (tmpdir, NULL);	
 		g_assert (store);
 		
 		g_assert_cmpuint (0,==,mu_store_count (store));
diff --git a/toys/mug2/mug.cc b/toys/mug2/mug.cc
index 63ffbecf..28fdab0d 100644
--- a/toys/mug2/mug.cc
+++ b/toys/mug2/mug.cc
@@ -66,7 +66,7 @@ reindex (MugData *mugdata)
 		return;
 	
 	err = NULL;
-	midx = mu_index_new (mu_runtime_xapian_dir(), 0, &err);
+	midx = mu_index_new (mu_runtime_xapian_dir(), &err);
 	if (!midx) {
 		if (err && err->code == MU_ERROR_XAPIAN_CANNOT_GET_WRITELOCK) {
 			g_warning ("database busy...");