Thanks for the hint! Never heard of my nokia, just saw it in the settings-menu and assumed it's deaktivated. (My last Nokia was a 9300 )

Well, that was a little strange.
The 2 messages from OP about failed sms delivery did only appear because the card was empty. With a charged simcard nothing appears and they don't get debited, was my fault (forgot about 2 sms transmitted that day). And on top of that my operator sends me exactly 2 sms with the gprs settings.

...
Does anybody know more about these two sms?
What is the content and recipient number?