Hello there akiraqc,

The ROGER on top of your phone is probably caused by a custom operator name, and I guess the previous owner of your phone was name Roger
You can find information about the package here: http://talk.maemo.org/showthread.php?t=33638

I don't know much about your operator, but there is an application to configure APN's:
http://talk.maemo.org/showthread.php?t=39951

Be careful when using this, playing with applications can cause problems sometimes. Be sure to read the documentation and disclaimers.

Hope this helps