The kext posted is like a driver with support for TRIM so it will not work only if there is something else that break it. I think that on 10.6.5 it could work. If I can I'll try it on 10.6.4 but before I have a lot of other works to do.
I belive that Magnifico sad that because of the subtitle of this topic, for what I know he doesn't have a 10.6.5 build to test it.
I have installed the 10.6.5 on the clone, does not work , but because you have fear of Apple store?