Each time I try to configure my mobile connected via bluetooth (usb way never worked) Wammu crashes.
What version of wammu are you using?
It's wammu-0.30.1-1
A little update. Trying 0.29 gives the same problems, in v. 0.27 wammu does'nt crash but in the end it shows error: Failure during opening the device. Device (here mobile's mac) does not exist, although wammu has found that.
Bug watches keep track of this bug in other bug trackers.
What version of wammu are you using?