This may not be related but I ran into a problem with notifications also and found a fix (actually saved the pointer when the post passed by). I didn't save the message reference and I don't have a copy of the error message I received, but this has a familiar "ring" to it.
Anyhow, if this problem is related, the fix is to the aolserver sendmail.tcl file:
# NOTICE NOTICE - change aolserver/modules/tcl/sendmail.tcl
# From: " _ns_smtp_send $wfp "HELO AOLserver [ns_info hostname]" $timeout"
# To: " _ns_smtp_send $wfp "HELO [ns_info hostname]" $timeout"
Randy
