Huawei e160g 3G usb modem trouble [solved?]

[spammed <spammed get2net dk>]

Hi,

I got this 3G modem after 'verifying' that it would work with networkmanager on Ubuntu 8.10:

http://forums.whirlpool.net.au/forum-replies.cfm?t=1046813&r=17127620#r17127620
http://tensixtyone.com/perma/howto-debian-lenny-huawei-e160g#comment-267 

However it did not work with my provider OiSTER.dk - when attempting to connect it would fail like this:

NetworkManager: <info>  Searching for a network...
NetworkManager: <debug> [1228941447.278901] nm_serial_debug(): Sending: 'AT+CREG?'
NetworkManager: <debug> [1228941447.288917] nm_serial_debug(): Got: '+CREG: 0,2
OK'
NetworkManager: <info>  Searching for a network...
NetworkManager: <debug> [1228941447.791863] nm_serial_debug(): Sending: 'AT+CREG?'
NetworkManager: <debug> [1228941447.802718] nm_serial_debug(): Got: '+CREG: 0,3
OK'
NetworkManager: <WARN>  automatic_registration_response(): Automatic registration failed: registration denied.

I extracted AT commands from a WinXP USB trace, which showed that while the CREG command would report "registration denied" the GPRS command CGREG would report connection status as expected.
The GSM 07.07 section on the CGREG command has the following note:

"NOTE. If the GPRS MT also supports circuit mode services, the +CREG command and +CREG: result code apply to the registration status and location information for those services."

So apparently GPRS registration succeeds while registration for circuit mode services fails. Can this be provider dependent? (Oister.dk provides a local data-only service.) Or maybe it is just a modem firmware bug?

Since the commands are so similar, I changed CREG to CGREG in the sources (specifically nm-gsm-device.c) as an experiment - and now it just works...
You should of course draw your own conclusions from this, but apparently there are cases where checking the CREG status is not enough. 

Best regards,
Jacob Nielsen 

Attached: WinXP USB trace and AT commands, nm-serial log, system info, patch.

Attachment: Huawei_E160G_Oister.dk.tar.bz2
Description: application/bzip-compressed-tar