I am not sure it is related, and I cannot test now since I don't have the HDSPA modem anymore, but on my pc I had the same problem (segfault in dmesg, no way to use it) and it started working just after I've run
sudo update-alternatives --config gcc
and choosing 4.7. I had also 4.6 installed (and set as default) because of CUDA 5.
I am not sure it is related, and I cannot test now since I don't have the HDSPA modem anymore, but on my pc I had the same problem (segfault in dmesg, no way to use it) and it started working just after I've run
sudo update-alternatives --config gcc
and choosing 4.7. I had also 4.6 installed (and set as default) because of CUDA 5.