struct ucred + macosx?

I tried to build Y--devel--0.2 (patch 54) on my macosx box. After 
working through some minor issues, I ran into Y/main/unix.c's use of 
'struct ucred'.

IIRC, Linux's 'struct ucred' is different than that of the BSD 
variants. (They don't have a pid field, the field names are different, 
so forth.)

Anyone dealt with this yet?

Thanks,
Dave