BigJ's 1.6u isn't a WM6 ROM, it's a WM5 rom. He's working on a WM6 release of his rom series.
The latest ROM he's produced is the 1.3h Zelda series ROM (kinda confusing on the versioning but it's the latest).
http://forum.ppcgeeks.com/showthread.php?t=8029 released 8-28-07.