It's not the same stuff - you shouldn't use white wine vinegar for cleaning (it's too damned expensive, for one thing!).
White vinegar is distilled, just like the malt stuff - white wine vinegar is fermented with real white wine. It won't do the same job and will bankrupt you if you try to use it in the same quantities you'll need for cleaning.
Ooh, I've had the same bottle on the go for at least six months. Then again, maybe that says something about my housekeeping... Lemme know how the shower curtain comes out - ours could do with a spin in the machine.