HidYn/Chris
1) Did you remove all contribs before upgrade (important) ?
2) If not, anyway, which contrib were installed on the server ?
Examining three of my Sme 8 (all of them upgraded from 7.6) no trace of mod_imap.so so I can suspect it was added by a contrib in 7.xx installation.
Anyway, as first attempt, try to put a comment before the load command in line 88 and restart your server.
Further verification -> take a look at:
/etc/e-smith/templates-custom/etc/httpd/conf/httpd.conf
/etc/e-smith/templates/etc/httpd/conf/httpd.conf
this might help to find the template fragment containing the mod_imap.so load command and to identify the cause of the problem.
Somebody here
http://forums.contribs.org/index.php/topic,48877.msg243443.html#msg243443 had the same problem but after a search in bugzilla I suppose he did not raise a bug.
Nicola