I removed the en.po file and then did an svn up. svn reported that it restored my en.po file.
I did another "make lang", and all the other languages bombed out except for English.
Looking at these language files, the other languages besides English appear to be patch files. The English file looks more like a simple list of messages.
Maybe svn is not properly applying the patches it downloads?
"svn help" yields the following information:
usage: svn <subcommand> [options] [args]
Subversion command-line client, version 1.3.1.
Type 'svn help <subcommand>' for help on a specific subcommand.
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