Hi all, I've bought the Passport International SIM card from Telestial. I just bought an unlocked treo 650 to be able to use internationally as well. I've tested other SIM cards in this phone and they work just fine. But, this Telestial SIM appears to work fine, it connects to a network, and so on, however whenever I attempt to make a call with it or whenever I am called by another phone the phone RESETS. Text messages work okay too, it is simply that the phone resets whenever I call or am called. Does anybody have any experience with this, or work-arounds for this?

Alternatively, any other good international SIMS which offer reasonable rates and work with the 650?