I understand everyones concern, and if you are worried I would not take the chance. According to my vet though, it is the same (advantage as well) my vet issues me large quantities and advises me how to dose it out for the cats and the dogs. I have never used frontline myself but asked because a friend had some, I have used advantage this way with no problems though. Had a scare once when another issue popped up at the same time.
ETA: A quick search pretty well advises against it, something about a tick med in the dog formula, not sure if that was the case back when I inquired or even if it is true as I was hitting mostly on other forums, but I would not risk it without contacting your vets office directly in case my advice was bad. I cannot personally attest to my it for frontline, only advantage.