Hi,
... hm... actually, they're _not_ the same. SH, i386, x86_64 and m68k have an extra FP state pointer after u_ar0 -- and m68k, Blackfin and H8300 all have 'int reserved' before u_ar0. The SPARC version is fairly different, too.
This would probably account for why mono-debugger won't build currently. Will the header be reintroduced any time soon?
TTFN
Paul