At webpage persan.nu there is a newsgroup, where some interesting things were revealed.
Show IMIE number
To view phone IMEI number enter *#06#
Easter Egg in WAP
If you choose 'Open location' in WAP and type 'details' and press OK you will get information about the two last errors.
To view phone network lock status
To view phone network lock status enter < * * < (wait 3 sec)
<**< Switch to the SIM Personalisation menu
ELogView.EXE
After installation of software (often a real buggy piece of software) there is a lot of applications that re installed but there is no documentation on anything. The application
"C:\Program Files\Ericsson\R380\Elogview.exe" I anyhow found amusing an useful, since if yoiu start it up, it is possible to select from Menu "Settings->Change logging settings" and thereafter specify "Log to a dialog" and change the logging level. This means that every time the software for communicating with the phone is doing something, there is a window shown. If logging level is set to 3 or 4, a lot of info on how the communication works is shown. Quite fun and good to know, when things dont work, what is wrong.