I plug in my phone over USB (which shows up as USB modem) and I see:

cdc_acm 1-2:1.0: ttyACM0: USB ACM device

however, Network Manager is apparently not detecting the device and is not offering me to connect to Mobile Broadband.

I verified that modem-manager is running.

Running Lucid 10.04 32-bit.

Any ideas? Extensive googling shows that it should "just work" in Lucid.