Hi,
I am having exactly the same error messages on a SunOS 5.8 box, with a site running openacs 4.5 and another openacs 4.6 (both PG)
The SMTP server is in another machine, where I do not have access and is quite secured so I am a bit blind on that front. The sys admin sent me the error message that looks exactly like yours.
where is the sendmail.tcl file, did that work?
