For some reason the latest OS 4.5 for the 8100 series is much harder to find online. I just got a tip from Secret Agent 003 that the latest OS 126.96.36.199 beta for the 8100 is now making its rounds on the web. Sadly this leaves 8110, 8120, & 8130 users out in the cold but at least OS 188.8.131.52 is around for the 8110 & 8120.
Point in fact of where you can find OS 184.108.40.206 for the 8100:
Let us know if you find any bugs
NOTE: Do not install this software if you do not know what you are doing. It may make your BlackBerry FUBAR or just plain angry.