Is there any limit to the number of Service Prinicpal Names that can exist on a Windows Server 2008 R2 box? Could some please direct me to documentation on the subject?

This document discusses the limitations of AD: http://technet.microsoft.com/en-us/library/active-directory-maximum-limits-scalability(WS.10).aspx I think the only limit would be approximately 1 billion total security identifiers (SID's) created over the lifetime of the domain. Richard Mueller - MVP Directory Services

totally unrelated and not in that doc.