Same thing here. I've been using iBluever on my iTouch an connects it to my N900, it had BT on all the time. Yesterday the said problem appeared, BT is off, cannot turn on, all pairings lost. After I found this thread, I deleted the mac address folder, and all was well. Because I had quite a bit of paired and trusted devices, and did not want to loose it, I overwrote the settings with my old settings, and it worked. But just after I used iBluever, it happened again. Now this time I did not restore my settings, but paired only my iPod and fired up iBluever. Sure enough it asked for permissions this time, and after I granted it, it worked just fine. So, I guess rather than iBluever, there wore some configuration errors...