post-commit stopped working after working great for months

I have been running subversion version 1.4.3 on linux since it was released.
My post-commit script for whatever reason stopped working about 4 days ago.
I changed it to simply echo the fact that it was running and still no
output. I can't find any changes in permissions and no error in
/var/log/messages and no mail for root. When I run it as the svn user like
this "env - post-commit /opt/svn/repo it works fine. I even rebooted the
machine which had been up for 162 days. Where can I go from here? Is there a
log file that subversion writes to that I could look at?

-- 
Dave Kallstrom