You didn't give us a lot of detail but I am guessing you have set up your system with a host name of "tripoz2" and a domain name "mine.nu". I guess also that you have a dial-up connection to your ISP at cjxxxxxx-a.xxxxxxx.xx.home.com and your system forwards all email to the smtp server there.
Again guessing, but are you trying to send email to a user at your own system? If so, qmail needs to be able to see that the destination address is at your own machine and therefore treat it as a local address. The local domain names can be set in the e-smith control panel under "virtual domains".
So in this case if you set "tripoz2.mine.nu" as a virtual domain then mail addressed to anyone at that domain will stay on your machine.
If all my guesses were off the mark then please ignore this message.

Phil Maley