ITIL was actually spawned from IBM's non-copyrighted Information Systems Management Architecture ISMA. If you'd like a copy of our article on the geneology of ITIL please send me an email and I'll dig out the article. The ISMA work was performed in the US by a dedicated IBM team and one of that team a Mr. Ed Van Schaak is a member of our Alumni and will be on our booth (again) at the 2005 Chicago conference.
At the 2004 conference we had a great session with many ITIL authors where the ISMA heritage was finally recognised. In principle the 5 major support practices (NOT PROCESSES!) were copy pasted, the Delivery side was reinvented. I feel the books accurately reflect this opinion.
Remember: ITIL is descriptive not prescriptive
Ian
ian@itsmi.com