Comment 3 for bug 655745

I have found the source of the problem. When I established the broadband profile, the Dongle had not yet been fully recognized by the kernel (it is a bit slow - need to start USB-storage and MMC devices, then activate the tty ports). As a consequence, it was created using device 0 (internal GSM). Thus, regardless of what network manager saw as currently active devices, it always tried to use device 0.

One problem is that the interface for defining profiles does not show to which device the profile is associated, nor does it allow changing it.

So rather than a true-blooded bug it's a conjunction of slow detection of devices and some user interface lacking relevant information and controls.