Glad you solved, but your thanks should be directed to Texstar, not me!
AndrzejL is right about kernel-2.6.38.8-pclos3.a64, probably is the better choice for you.
I was referring to the family 2.6.38.8-pclos3, which include the former + .a64, .bfs, .pae, .pae.bfs, all are patched for athk5.
AS