Differences between FSFS filesystem format version in Subversion
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I just upgraded my svn server to 1.6 with Collabnet Subversion Edge and I found a difference between the old and the new repostory :

 - old : Filesystem Format : FSFS version 2 / Repository Format : 5

 - new : Filesystem Format : FSFS version 4 / Repository Format : 5

What is the difference between that two repository ? Can I upgrade it ? (and is it a good idea ?)