I'd see no problem with someone else's brand on my beer, like Buckley's brand on O'Hara's.
But I do think that I'd have a problem with re-badging one of my own [i:v8hu9ipo]products[/i:v8hu9ipo]... I'd rather create an original beer, and then stick their brand on it. A good example is O'Hara's and Aldi. The Aldi beer is not that different from O'Hara's Red, but different enough not to be the same product.