Someone made a new initrd creation script and posted it here: http://www.poochiereds.net/svn/lvm2/ I can't guarentee it'll work, but i've heard good things about it. Use it against the 2.6.5 kernel you compiled.
I've created a new version (incl. svn diff) of the script here: http://wwww.morch.com/postings/lvm2/
-- Peter Valdemar Mørch http://www.morch.com