My thought... You have got dnslookup turned on, but have no reverse dns
configured for that zone - and or you have ident lookup turned on and it's
not working right.
it is port 113 which times out or refuses... therefore it is the ident
I had this problem a few days ago: after installing a new WAN router
with internal firewall connecting the SMTP server took 30 secs until the
SMTP greeting appeared in telnet. Solution is to add "-noidentlookup" to
TCPDOPTS in /etc/courier/esmtpd (or whereever the file is.)