The REPORT request returned invalid XML in the response: XML parse error at line

I've been reading threads on this topic and have tried many of the
suggestions without any positive results.
Our game development company has been enjoying SVN for a year now. We have
many repos of various sizes. Clients one three platforms. We currently use
SVN clients on WinXP, WIn2000, Fedora 3 &4, and Max OSX 10.3.9

Our error is with our larger Repo named Art which is 3.8 GB, [ 1283
revisions ] - running on Subversion 1.2.1 (r15230)#਀
We are accessing this via apache_2.0.54-win32-x86-no_ssl

WinXP and Fedora run fine.
I'm having trouble with our Mac client.
Mac SVN is version 1.2.3 (r15833)
Link: http://metissian.com/projects/macosx/subversion/

The error we are getting should look similar to what I have seen in threads
already:
svn: REPORT request failed on '/svn/Art/!svn/vcc/default'
svn: The REPORT request returned invalid XML in the response: XML parse
error at line 17526: no element found (/svn/Art/!svn/vcc/default)

Changes made after reading threads:

Apache changes:
Timeout 60000
KeepAlive off
MaxKeepAliveRequests 0
KeepAliveTimeout 150000

SVN Client changes:
on Mac only: ~/.subversion/servers
uncommented [global]
http-compression = no

I can pick directories to checkout to avoid the point of the failure
directories, but this is not a good solution, because I need the two
directories were it is failing. SVN cleanup and then SVN update do not do
the trick. It fails every time at the same place in both sub-directories
that I have found. Even after making the above changes to both the SVN
client and the Apache server (saved - shut down / restarted) I have also ran
SVNADMIN recover on the Art repo too.

Modules enabled in Apache:
LoadModule dav_module modules/mod_dav.so ( version info
2.0.54.0<http://2.0.54.0>)
LoadModule dav_svn_module modules/mod_dav_svn.so ( version info 1.2.1.15230)
LoadModule authz_svn_module modules/mod_authz_svn.so ( version 1.2.1.15230 )

-- 
- lan