Hi guys
thanks for the help so far
but

1.
the portforwarding part is NO problem - it works with above line on the N900 as it works on my laptop

the remaining problem is getting mail OUT

localhost may have NO mail agent to handle mail locally for forwarding

2.
I tried repeatedly to change various ports on my mail server
among others also rfc alternate port 587
and a few others

i walked through a complete telnet smtp session on my laptop successfully using alternate port

but on my N900 it seems that the provider blocks just anything related to outgoing mail independent of port
on the mail server there are NO error message at all when attempting to send mail from N900

and of course the receiving of mail works perfectly from N900

personally when comparing alternate port to portforwarding using a secure tunnel. I prefer ssh portforwarding as in my laptop to ensure nothing is sent clear text.

so maybe I have to install postfix or something comparable on my N900 to send locally and use pfwd ?
anyone experience in such procedure with N900 ?