After running through a lot of merges last night (I was incrementally going through several changesets to see where I'd introduced an interesting regression) and updating to the HEAD revision and fixing the bug, I got the following error message while trying to commit:

svn: Commit failed (details follow):
svn: Your file or directory 'paypal.py' is probably out-of-date
svn: The version resource does not correspond to the resource within the transaction.  Either the requested version resource is out of date (needs to be updated), or the requested version resource is newer than the transaction root (restart the commit).

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