I used the file provided by looser and it worked. The margins are smaller now, so
Now, I would like to make the margins even smaller. Does anybody know which bytes should be changed for left and right margins ? (I've seen ixtab's entry on the first page but in looser's file, the numbers for left and right are unchanged

and it still works)
a note : if you change the 'words per line' setting from the menu, you have to copy the file again in /var/local/java/prefs.