I haven't fixed the problem yet. But I did appreciate your story. It gave me a few more ideas of things to try. I'm still hoping not to go on any more of a recompiling rampage than I already have. It tends to be a whack-a-mole type game.

I did try strace/truss/gdb, but nothing struck me as obvious.

I tried running from the command line and CGI very early in trying to solve this and forgot about the output. Which may be more useful because it probably means this isn't strictly a mod_perl issue.

Here is the error I get using CGI (non mod_perl):

DBD::Pg::st execute failed: PQsendQuery() -- There is no connection to
+ the backend. at /usr/lib/perl5/site_perl/Apache/Session/Store/DBI.pm
+ line 65.
[download]

I think that if I can get this working under vanilla CGI, then mod_perl will work aswell.

Thanks for the help,
Staunch