I found this recipe in a newspaper. It makes very soft, lime flavored cookies. You might want to taste the lime juice you're using - I think the strength can vary, because, once when I made it, I couldn't taste the lime at all! The other times it has come through just fine. You can also substitute lemon juice.
Note: I just made these cookies again and ended up with wonderfully soft, fluffy sugar cookies (read: no lime flavor at all). I'm hereby considering this recipe under construction, and may edit it to reflect some tinkering (with extracts or concentrates).