export CLASSPATH=/your/stuff/

or preserving system wide settings:

export CLASSPATH=$CLASSPATH:/your/addition/

the only different from Windows in terms of path-separators, : instead of ;

For example

java -classpath /mydir/mylib.jar:/otherdir/otherlib.jar com.MyProgram -Xmx64m

wildcard in the classpath to add multiple jars


java -cp "Halo.jar:lib/*" ni.package.MainClass

More about classpath...

http://net-informations.com/java/basics/path.htm

Anto