Building Ruby with dtrace on OS X

Has anyone built ruby with dtrace support on os x? I haven’t been able
to get it working. The only source I’ve found is at joyent
(http://svn.joyent.com/opensource/dtrace/ruby/ruby-1.8.6/). When I try
to build it it fails on a dtrace step, because OS X’s version of dtrace
doesn’t have the -G option. So I changed it to -h hoping that would
work, but I get the following error:

dtrace: failed to compile script dtrace.d: line 27: extraneous argument
‘version.o’ ($37 is not referenced)

No clue really what to do. Doesn’t seem to be any info out there,
because the OS X built-in ruby already has dtrace support. But I’d like
to build it myself. Anyone know how?

Pat