python-gammu now supports service numbers dialogue. How it is useful for you depends on services your network provides. For example with Vodafone in Czech republic, you can use it to configure various services:
$ ./service-numbers.py
This example shows interaction with network using service codes
Enter code (empty string to end): *111#
Talking to network...
Network reply:
Status: ActionNeeded
Vitejte v Kapesni Samoobsluze!
1 Muj ucet
2 Me sluzby
3 Nastaveni telefonu
4 Info a zabava
5 Oblibene
Enter code (empty string to end): 1
Talking to network...
Network reply:
Status: ActionNeeded
Muj ucet
1 Vyuct. a platby
2 Vydaje pod kontrolou
3 Osobni udaje
4 PIN a PUK kod
------
0 Zpet
00 Uvod
Enter code (empty string to end):
Python code which can be used for this is available as example. It will be probably one time integrated to Wammu, but it needs a bit more time than hacking this simple script :-).