There is a fix in the open source version of 2.0.46
http://www.apache.org/dist/httpd/httpd-2.0.46.tar.gz
...which allows coredumps on Linux when you start httpd as root and code CoreDumpDirectory in httpd.conf. If you start httpd as non-root, it should just work (i.e., you don't need the fix), assuming CoreDumpDirectory points to somewhere like /tmp where the non-root user can create files.
oooops. This fix is mainly to os/unix/unixd.c::unixd_setup_child() . That function is not called by the perchild mpm, so it won't help your situation.
I'm assuming perchild does its own setuid calls, since the user ids are a unique feature of perchild. You could look for this and code prctl(PR_SET_DUMPABLE,1) after the setuid. Here's what I did in the mainstream code:
http://cvs.apache.org/viewcvs.cgi/httpd-2.0/os/unix/unixd.c.diff?r1=1.56&r2=1.57&diff_format=h
Good luck!
Greg "not about to become the PerChild maintainer" Ames
