rpm package file for cyrus-sasl-gssapi-2.1.22-5.el5.4.0

I completely understand what you're attempting to do, but please understand that the installation of software packages, of any kind, is unsupported on these platforms. There is no license to install or make available an RPM. You can attempt to, and potentially succeed in installing separate unsupported software packages, but there's an almost 100% guarantee that they won't produce the results you're looking for in the product. If you want to achieve Kerberos authentication to your SharePoint servers, the best (and only) way to do that is by licensing and provisioning APM. I think you'll find the configuration for APM Kerberos to be reasonably easy, and absolutely supported.