hi chicoicho,
me, you and too many 8800 user has the same problem. Bluetooth does not working with os 4.5. 8800's which produced in Hungary have this problem. And very very thanks to rim, rim didn't fix this problem, and don't answer the questions. Rim didn't do anthing. Thank you rim!
Sometimes connecting it with other phones it got some curroption in the internal setting and files of it. It is also possible to check out it of the latest version of it may be it could be happens due to it.