Problem with ._ files on Mac OS X and SVN Autoversioning on

Hello.
I'm hoping the list can help me with an issue we're currently having.

The scenario:
Server: Mac OS X Server 10.4.3, Subversion 1.3.0 with Apache 2.2.0
and APR 1.2.2, all built from source. FSFS repository, sitting on
Adic StorNext/Apple Xsan filesystem.

To enable easier access for some content developers who must work
through SSL VPNs, I recently enabled SVN Autoversioning.

The Mac OS X users can mount the WebDAV share just fine, and their
changes are committed successfully.
However, since Mac OS X doesn't think the WebDAV server can handle
xattr information, it creates ._ files on the WebDAV share, and these
are dutifully added to the repository.
The problem then appears when a Mac OS X user using standard
Subversion (rather than the WebDAV share) attempts to update their
working copy.
They receive errors such as
svn: Can't copy 'assets/48/final/.svn/tmp/text-base/._.DS_Store.svn-
base' to 'assets/48/final/._.DS_Store.tmp': No such file or directory

I've read the threads on the developer list regarding resource forks,
non-HFS+ filesystems, ._ files, and xattrs, but this I didn't see
this particular scenario mentioned.

Does anyone have a suggesstion as to how to prevent this problem? Are
commit hooks invoked when using autoversioning? If so, could I create
a hook that would silently neglect to commit the ._ files?

Thanks
-lilmatt