I have tested the problem with a barebones build of httpd on
FreeBSD 5 and 6. I do not believe any different library versions
are shared between this module and Apache or other loaded Apache
modules; symbol conflicts were my first thought.
No idea why... but I've definitely encountered that exact
situation before with a few different modules on osx/freebsd. I
just never had time to explore.
It's definitely a symptom of the bootstrapping of XS. But it
doesn't happen under MP1, just MP2.
I retract this. It happens on both mp1 and mp2.