Wasn't there a weapon speed hack in Warband Beta? Maybe I'm confusing it but somehow you could edit weapons. It's fixed now though.
Weapon speed hack? if there was, it wasn't on the NA side. I can't speak for the EU admins, but I know for a fact that this was never recorded or mentioned in our records.
The weapons editing glitch was in the beta, but thats a bit different. There were several restraints on it, and it had to have been a native weapon recognized by the server. In otherwords, you couldn't take a katana and edit its attack speed to over 9000. If you brought the katana to the beta server, it would have the same stats as a regular katana in native.
This bug was fixed a long time ago though, well before c-rpg was a twinkle in chadz' eye.