Installation fails make test-all

I’ve been provided a new computer by my IM group. They installed and
configured CentOS5. When I install Ruby and run the tests all of the
soap related tests fail. I need this to work for the Redmine gem.

This does not happen on the old CentOS4 computer. Since the ruby tarball
is the same I have to assume that something that ruby looks for when
configuring is missing on the CentOS5 configuration. However, I don’t
know what.

How do I determine just which package(s) are missing from my
configuration to get the ruby installation to perform as it did on the
older system?