problem with apt-get

["Philipp Hug" <debian@hug.cx>]

when I to put stable, testing and unstable into /etc/apt/sources.list I get
the following error:
E: Dynamic MMap ran out of room
E: Error occured while processing space-orbit (NewVersion1)
E: Problem with MergeList
/var/lib/apt/lists/localhost:9999_debian_dists_unstable_main_binary-i386_Pac
kages
E: The package lists or status file could not be parsed or opened.

In this example I'm using apt-proxy, but the same error occurs without
apt-proxy.

Is it not allowed to have all 3 releases in the sources or is this a bug?

philipp