I don’t know the best answer. Ant is quite cool, but I’ve only made use of it in a limited way, kind of cook-book plugging into existing examples. It seems like a very useful tool, and have only been held back by the learning curve and my tendency to forget how to work with things I don’t use often, and the Eclipse tools work for 98% of what I need to do (so far).
Here are two additional suggestions:
(1) Eclipse has a responsive forum for questions.
I’ve always had good luck at the Newcomers area. Please do post the answer here if you get it solved at that site!
(2) JarSplice is quick to download and easy to use and can very likely handle your issue. http://ninjacave.com/jarsplice
I was initially resisting going here, but was very pleasantly surprised when I finally gave it a try.