The javac2 task seems to re-write the class file even if it is already augmented with the correct class code.
In itself this is not a problem but if the class files are jarred afterwards the jar task detects a change and rejars the files. This makes (re-)builds slower then they can be.
I always try to keep my builds as clean as possible, which means that they do as little as needed. Most tasks (like javac and jar) check if work needs to be done from the timestamps. I can not find a way to make the gui designer compiler NOT change the class file when not needed. This ripples through my build and takes up precious time.
Request: let the javac2 ant task refrain from updating class files if not needed.