Complete factory reset on 6510

I'm selling my old 6510 and I'd like to know if there's anyway to completely reset all the settings on the phone.. i.e. delete all messages, custom ringtones, SMS templates, logo pics etc..? I don't have any data cables or anything like that.. just the phone (and i know the security code). Is it possible?

did you try restore factory settings on phone settings?

Yes but it still leaves a lot out. It restores the settings to their original, but doesn't remove custom ringtones or the other things I mentioned.