I did try what you suggested, it didn't help. In fact, I did a factory reset (for another reason) and it didn't help, either. It is possible that the bug was related to GB - hard to say if it was the app itself or Samsung's version of Ginger Bread that was causing this problem (at the time of writing I was running the original kernel and ROM by Samsung). Judging by the lack of other responses, it could have been an isolated case. I have a new ROM and kernel on my phone now (ICS 4.0.3-based) and I do not experience this problem anymore.

Thanks,

Chris