subversion problem svn: Malformed network data

every time I do commit project with subversion as vcs, I get
Error:svn: Commit failed (details follow):
svn: Malformed network data

however, everything is correctly committed into the repository.
workaround is to do update project, then IDEA "makes all files black" and all is ok.

Subversion Server = svnserve, Version 1.4.2 (r22196) on Fedora Core 6

Anybody has an idea, why this occurs and how to fix it?

Is the svn plugin incompatible with Tortoise SVN?
Seems like adding a directory via Tortoise SVN, or calling an update via Tortoise,
-> IDEA thinks the folders are no longer under version control.