numbers. The r4337M is because it's a svn snapshot of a branch. I would think the M is because it's from svn and the repository is modified from 4337 (smells like 'svnversion' output). Branches would be a branch name. I concur with Roland - use the svn version rather than the date - the closer you can track upstream. the better. The real issue is that you need a plan that all revision numbers that will ever come from upstream, when mapped into your scheme, will have the right sort order.
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