I am trying to use the 64 bit rxtx serial communication library (downloaded from cloudhopper) with 64bit windows 7 and eclipse. I get the message:
java.lang.Unsatisfi
Windows user : my problem was actually that I was placing the rxtxSerial.dll and the rxtxParallel.dll files in the wrong directory.
In my case, they were in [...]/jdk1.7.0_09/bin/ instead of [...]/jre7/bin/, although paths may differ for different versions of Java.
After all it's logic, if we want our JAR to run outside our IDE, we must have the dlls in our java running environment, not in our development environment :)