I think that the problem is following: the 3g dongle can work either in a usb-storage mode or 3g dongle mode. You need to somehow tell the dongle that you want the 3G functionality. I do not know if network-manager has such functionality but it would be highly appreciated. Last time I tried, I was unable to get the huawei dongle to work on my ibm thinkpad T43/p.
I think that the problem is following: the 3g dongle can work either in a usb-storage mode or 3g dongle mode. You need to somehow tell the dongle that you want the 3G functionality. I do not know if network-manager has such functionality but it would be highly appreciated. Last time I tried, I was unable to get the huawei dongle to work on my ibm thinkpad T43/p.