To program for JAVA J2ME using Eclipse under Ubuntu following the guides in the following links should help with any problems encountered. This assumes you have already installed Eclipse. (can't remember the exact problems I encountered, but you have to edit a settings file somewhere or making a symlink (Se the ProGuard links))
http://www.autexier.de/jmau/dev/j2me/j2me.html
http://eclipseme.org/docs/refPrefJ2ME.html
http://blogninja.com/doc/libproguard-java/manual/wtk.html
http://dev.eclipse.org/newslists/news.eclipse.dsdp.mtj/msg00507.html