you need 3 files. TCPMP player (rc 072...or something like that), the latest version of flashvideobundle (ive come across 2 versions...the 1st doesnt work...the second is perfect), and TCPMP flv plugin. Once these are installed (I would recommend installing all 3 to the device) you will have to go to the desktop version of YouTube...the mobile version wont work.

Search the forum for "Full Youtube Access"...you should be able to find the files you need.