The current stable version of bt747 seems to be 2.1.1, cf. http://sourceforge.net/projects/bt747/files/ Simply copying the current ebuild to "bt747-2.1.1.ebuild" works, the new version installs fine.
Created attachment 394760 [details, diff] bt747-2.1.3.ebuild.diff Current stable 2.1.3, according url. Also, to run simpler, I add creation of desktop file. Without icon for now - should be downloaded from net and converted from gif to png...
Good news. I needed to bump this in order to remove Java 6 (because of jcharts) so I've given it the full works and now all the libraries are unbundled. Just need to do some finishing touches.
Done. I added the icon but stuck with gif, nothing wrong with that.