I have been asked to try packaging a patched upstream code for that driver, I took the code from git clone git://anongit.anholt.net/git/rt2860 and uploaded the result to my PPA: https://launchpad.net/~stgraber/+archive
I used cdbs for the packaging, we'd need a clean orig.tar.gz before considering inclusion in Intrepid's current kernel (and an UVFe too). Anyway, the package in my PPA is clean and seems to work almost perfectly on current Intrepid.
It has so far been tested successfully with WPA2+AES and roaming (WDS) seems to be working too.
Note: I don't know the code and at first sight it seems far from clean, I had to hack the Makefile to have it generate files in the right place.
Hope it helps.