Thanks, yeah that's what I did in the end. Swept all the private keys twice. Still lost about four bitcoins in the process, no idea where they went to. Bitcoin QT does not register this and still tells me it has all my bitcoins right here. Really well programmed.
This is the second time I lost money with btc. First time I split my btc between my own wallet and some online service called 'mybitcoins.com'. I figured you can't be too careful and I should keep a few with a third party in case I have a fire or get burgled or whatever. Few months later they were all
'Ooh dear , I got hacked and lost all your bitcoins.'
Yeah, fantastic, buddy. Don't worry, though, it's only money, eh?
OK, I still have made more money than I lost and I guess you pay the price for crappy services you get with bitcoin this early. Still feels rubbish to lose money in such a way, though.