Configure sendmail to work with telia
 

Hi I don't know if this relates!
But try this. It worked for me after some struggle.

1, Change domanname to example.com (since I don't own an domain myself)
2. make sure this line exists in /etc/mail/sendmail.cf :
DSsmtprelay1.telia.com (or your IPS relayserver)
restart sendmail script
type as user mail -s "This is a servertest"
Hello this is a test from Server"
CTRL -D
CTRL -D

3.Now your hopefully ready to go!