help with jlex

I am new to creating scanners and I am looking for help from anyone with experience JLex. I am having problems running the sample file provided on the princeton installation guide. It doesnt recognise files created by JLex although they seem to compile into lex files and then java files correctly. Has anyone else tested this file, it is possible that it is just that this file is faulty. I am in the process looking at other scanners at the moment which are also constructed in JLex, maybe I will find my solution there.

Any help would be greatly appreciated.

Cheers