error after install: MDK 9
 

Warning: -jar not understood. Ignoring.
Exception in thread "main" java.lang.NoClassDefFoundError: RunLime.jar
at 0x4026e420: java.lang.Error.Error(java.lang.String) (/usr/lib/libgcj.so.3) at 0x402702d0: java.lang.LinkageError.LinkageError(java.lang.Stri ng) (/usr/lib/libgcj.so.3)
at 0x40271960: java.lang.NoClassDefFoundError.NoClassDefFoundErro r(java.lang.String) (/usr/lib/libgcj.so.3)
at 0x402c8edf: gnu.gcj.runtime.FirstThread.run() (/usr/lib/libgcj.so.3)
at 0x4026177c: _Jv_ThreadRun(java.lang.Thread) (/usr/lib/libgcj.so.3)
at 0x402283bc: _Jv_RunMain(java.lang.Class, byte const, int, byte const, boolean) (/usr/lib/libgcj.so.3)
at 0x0804882f: ?? (??:0)
at 0x40675082: __libc_start_main (/lib/i686/libc.so.6)
at 0x080486c1: ?? (??:0)



what should I do to fix this? someone please help