Java Help

[Tommy Herrmann]

Hey all!  I'm trying to run a private RuneScape server/client on Ubuntu 
Dapper but I keep getting this:

tommy at dad:~/Desktop/Moparscape$ java -noverify -Xmx500m -cp 
./MoparScape.jar: Bot 0
Exception in thread "main" java.lang.NoClassDefFoundError: 
java/lang/StringBuilder
        at Bot.<clinit>(Bot.java:107)

Dad suggested I consult the list and I figure someone knows what I'm 
doing wrong.

The site I got the client from is:
http://www.moparscape.org/smf/index.php/topic,6915.msg70691.html

Gurus bestow thy knowledge!!

                      Tommy