Subversion Exception!
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Subversion reported the following
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In file
line 1596: assertion failed (! svn_path_is_url(relative))

I'm on Windows XP, TortoiseSVN 1.6.99, build 22019 - 32bit dev - 2011/09/22 12:01:54
Subversion 1.7.0 -dev
apr 1.4.5
apr-utils 1.3.12
neon 0.29.6
OpenSSL 1.0.0d 9 Feb 2011
zlib 1.2.5

Steps for the crash:
1. I opened Show Log dialog on my checkout
2. Selected last revesion (I committed it)
3. Right-clicked on the file I committed (only on file was in commit), and chose "Revert changes from this revision"
4. There happens crash!

Hope this helps