Use the abbrevs file to modify an existing abbrevs file in the .jedit folder, edit as you wish. Put the macros in .jedit/macros folder and the PYP5.xml in .jedit/console/commando folder (you will of course needed to install the jEdit console plugin).
Using the Macros
Once installed you will find you can access the macros via the jEdit menu-bar, or a shortcut key if you wish. The sketch path is picked up form the displayed buffer (so any new sketch should be saved). You need only set the path to java and path to the processing.py jar once as they will be "remembered" in subsequent runs, easy peasy. Click on the Commands tab to see what options are included on the command line (modify the PYP5.xml commando file if you need to send args at runtime).
|The PYP5 commando dialog box (loaded by PYP5.bsh macro)|
Since updated here.
|Running processing.py from jedit (pre processing-2.0b7 core.jar)|