Ruby on AIX. Again

Since AIX now supports RPM as a package format, I would like to build a RPM of 1.8.5 that I can install on a number of systems. So far, I have been unsuccessful at finding an existing SRPM of Ruby for AIX. Quite likely I'm not looking in the right place. So, any suggestions for where to find a SRPM of any version of Ruby for AIX?

If I can't find that, I will probably try modifying the SRPM that is used for CentOS 4.4. Any words of wisdom about it?

-- Matt
It's not what I know that counts. It's what I can remember in time to use.