After upgrading to 10.3.8, my own compiled mod_perl stopped working. If you compiled your own as well, and find it broken, here's how I got mine working again:
$ sudo cpan
cpan> install Bundle::Apache
cpan> exit
$ cd /usr/local/src
$ sudo wget http://perl.apache.org/dist/mod_perl-1.0-current.tar.gz
$ sudo gunzip -c mod_perl-1.0-current.tar.gz | sudo tar xvf -
$ sudo perl Makefile.PL USE_APXS=1 WITH_APXS=/usr/sbin/apxs \
EVERYTHING=1 NO_HTTPD=1
$ sudo make
$ sudo make install
$ sudo apachectl restart
Enjoy!
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