setgroups error in Rsync: Configuration or Missing Part?

[Catalino Cuadrado]

I've been trying to get my two Mac OS X computers to sync using rsync
2.5.5. I have one set up as the host with --daemon and the other with a
client running. I was encountering an
 @ERROR: chroot failed error in my messages. I found that the problem lied
in a misconfiguration of the rsyncd.conf file. I had tried to specify a
POSIX pathway using the quoted foward-slash method. Once I got past that,
the next error was @ERROR: setgroups failed. However, unlike chroot, I
don't have this program on my system. I've looked on the 'net, and only
found setgroups defined as a c function setgroups() which seemed to be
part of the rsync raw source code. Is this an error in the rsync program
or am I missing an external program? Where can I download this
program/complete source code for this program?
-Tito