Give more details if you still want help:
What version of Java?
What version of Limewire?
What Linux Distribution?
What directory are trying to start Limewire in?
Is Java properly installed?
What results do you get when you type "java -version" into a console?
What results do you get when you type "whereis java" into a console?
What results do you get when you type "echo $PATH" into a console?
Answers to these questions would help a great deal in trying to figure out what's wrong.