Simply put, every time I have used the Faust's charge attack in a Lockdown game, the blade has always detonated instantly. Don't know about Gran Faust or the Avenger line, so if someone can test those to see if it's Sealed Sword in general that'd be nice.
Same goes for DA/Avenger/Gran Faust Charge, I think OOO is aware of this.
Submit a bug report via F2 if you already havn't, thanks!