what is your exact version of java on the server?
because i test here and i can load you solution under windows just fine with java 6 (1.6.0_02-b05) and java 5 (1.5.0_08-b03).
But i also tested it with linux and java 6 there worked fine but java 5 (1.5.0_06) also fails.
So it seems that you have a pretty new java 5 on the server and somehow this makes files that are not compatible anymore with older versions of java..
If you use a java 5 version greater then 1.5.0_07 then you could downgrade to 1.5.0_06 or something OR upgrade to java6 because we have special support for Server java6 and Client java5.. So these things don’t happen.