RT stops sending email

This seems to be a rare occurrence, but our RT install sometimes stops
sending email. I have to restart Apache or kill the fastcgi processes
and let them restart before it will resume. RT 3.8.7, Apache 2,
fastcgi, and I’ve changed it to use sendmail instead of the default
sendmailpipe (happened more frequently with sendmailpipe, but still
happens with sendmail)
Set($MailCommand , ‘sendmail’);
Set($SendmailArguments , “-oi”);

I see this in the logs when RT attempts to send an email:
Jan 13 13:18:28 rt mog_rt: Scrip Commit 10 died. - Can’t fork at
/usr/share/perl5/Mail/Mailer.pm line 137. Stack:
[/usr/share/perl5/Mail/Mailer.pm:137]
[/usr/share/perl5/Mail/Internet.pm:451]
[/home/rt/mog_rt/bin/…/lib/RT/Interface/Email.pm:503]
[/home/rt/mog_rt/bin/…/lib/RT/Action/SendEmail.pm:307]
[/home/rt/mog_rt/bin/…/lib/RT/Action/SendEmail.pm:129]
[/home/rt/mog_rt/bin/…/lib/RT/ScripAction_Overlay.pm:238]
[/home/rt/mog_rt/bin/…/lib/RT/Scrip_Overlay.pm:464]
[/home/rt/mog_rt/bin/…/lib/RT/Scrips_Overlay.pm:196]
[/home/rt/mog_rt/bin/…/local/lib/RT/Transaction_Overlay.pm:188]
[/home/rt/mog_rt/bin/…/lib/RT/Record.pm:1457]
[/home/rt/mog_rt/bin/…/lib/RT/Ticket_Overlay.pm:3323]
[/home/rt/mog_rt/bin/…/lib/RT/Ticket_Overlay.pm:2996]
[/home/rt/mog_rt/bin/…/lib/RT/Record.pm:898]
[/home/rt/mog_rt/bin/…/lib/RT/Interface/Web.pm:1340]
[/home/rt/mog_rt/bin/…/lib/RT/Interface/Web.pm:1450]
[/home/rt/mog_rt/share/html/Ticket/Display.html:155]
[/home/rt/mog_rt/share/html/Tick

(the line appears to be truncated in the logs)

Has anyone else seen this?

Oh boy, the subject should have of course be different…

Mgr. Martin Drasar drasar@ics.muni.cz
CSIRT-MU, Network Security Department http://www.muni.cz/csirt
Institute of Computer Science, Masaryk University, Brno, Czech Republic
PGP Key ID: 0x944BC925