There is now a new kernel in http://people.canonical.com/~smb/bug476154/ and this new kernel (ie linux-image-2.6.31-16-powerpc_2.6.31-16.51+bug476154v1_powerpc.deb) solves my shutdown issue for b43legacy on my powerpc laptop. See bug 476154 for more discussion.
There is now a new kernel in http:// people. canonical. com/~smb/ bug476154/ and this new kernel (ie linux-image- 2.6.31- 16-powerpc_ 2.6.31- 16.51+bug476154v1_powerpc.deb) solves my shutdown issue for b43legacy on my powerpc laptop. See bug 476154 for more discussion.