Hello Ben,
I need to use mysqldump to back up the wiki. So -- how can I upgrade my mysql4 database to one of the new mysql 5 schemata?
We have few mysql5 servers running around, that got imported from mysql4 data.
Though we do a bit different trick (we start server with --default- character-set=binary, then load binary data - mysqldump can give you a binary dump too) - essentially it is quite similar to the binary schema inside MediaWiki package.
So, you either have to do binary dump if you want to reimport into properly built MySQL5 instance, or you can use Special:Export / other xml dumping tools.
The problem with standard mysql4.1+ mysqldump is that it dumps data as 'utf8' by default - to conversions might be done on fields that were tagged as 'latin1' before.
Best regards,