multiple definitions of _warn ?

I'm getting a lot of this on the recent compile on OSX:

  /usr/bin/ld: warning multiple definitions of symbol _warn
  libgit.a(usage.o) definition of _warn in section (__TEXT,__text)
  /usr/lib/gcc/i686-apple-darwin8/4.0.1/../../../libSystem.dylib(err.So) definition of _warn

Is that just expected, or an indication that there's a portability issue,
or something else entirely?
-- 
Randal L. Schwartz - Stonehenge Consulting Services, Inc. - +1 503 777 0095
[off-list ref] <URL:http://www.stonehenge.com/merlyn/>
Perl/Unix/security consulting, Technical writing, Comedy, etc. etc.
See PerlTraining.Stonehenge.com for onsite and open-enrollment Perl training!