Do you need Tomcat6? It's available over at www.jpackage.org, and will be in CentOS 6. Not that this deals with your issue, but I thought you might appreciate a heads up on its availability as a more contemporary version to aim for.
Thanks, Nico, I will stick with CentOS5 onboard tools for now, although the service will undoubtedly move to CentOS6 in the medium term.