We have tried but unfortunately there are many compatibilities issues from one platform to another and from one JVM to another. Java promise of write once, run anywhere is not quite realized for complex program like TRiLOGI unless you tweak and develop for each platform.
Even on Windows PC, moving from JRE 1.3.1 to JRE 1.4 bring some incompatibility and we received feed back that TRiLOGI could not run properly when tested on JRE 1.5 on a Windows PC. In addition, there are many different Linux platforms, so to claim the TRiLOGI can work on Linux will give up a potential support nightmare when you compute the combination of different linux and different JRE versions.
With the introduction of XServer, there is even less reason to introduce a linux solution since XServer will provide a low cost, standalone platform to connect the PLC to the Ethernet network all in the space less than that of a small pack of cigarette. Before XServer there were calls for Linux support of TLServer so that an old PC can be used as Internet gateway for the M-series PLC, but the Xserver will eliminate that requirement. An old PC running Linux still draws maybe a 100W when idling!