A friend of mine recently called me 3 times in a row while I was working, so I didn't answer. After the 3rd call, I got worried that something was wrong, so I called her back. She said something to me that made no sense, about being almost at the restaurant (we were not meeting). It took a minute to realize she thought she was talking to her other friend with my first name.

I teased her the next time we talked. Not only do I think it's acceptable, but required to tease your friends. If they don't take it well, tease more. Eventually, they'll either get it, or they'll stop being your friend (good riddance).