Now GAJET can be launched as task from Ant build file using <gajet> task. Working example of build file as well as <gajet> task description can be found inside GAJET distribution.
Here: http://sourceforge.net/docman/display_doc.php?docid=61770&group_id=155208 you can find simple step by step example that shows how to use GAJET.
After a year of hidden development, current version of GAJET published on SourceForge. I hope, starting from this point, development of GAJET project will proceed in open-source style and spirit.