diff --git a/requirements.txt b/requirements.txt
index 1e2a2ae..9e0b5f7 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,5 +1,5 @@
-# Requirements
-six
+# Minimal requirements defined in setup.py
+-e .
+# Extra "optional" requirements
 gssapi[kerberos]
 portalocker[cygwin]
-rfc6555
diff --git a/setup.py b/setup.py
index 9080410..30be722 100644
--- a/setup.py
+++ b/setup.py
@@ -58,6 +58,11 @@ class TestCommand(Command):
         #TODO: failfast does not seem to exist in python2.6?
         TextTestRunner(verbosity=2,failfast=True).run(suite)
 
+reqs = [
+    'six',
+    'rfc6555'
+    ]
+
 setup(name = "offlineimap",
       version = __version__,
       description = __description__,
@@ -71,6 +76,7 @@ setup(name = "offlineimap",
       scripts = ['bin/offlineimap'],
       license = __copyright__ + \
                 ", Licensed under the GPL version 2",
-      cmdclass = { 'test': TestCommand}
+      cmdclass = { 'test': TestCommand},
+      install_requires = reqs
 )