Do you still put your source code in the io package and mapred package ?

If so, rebuild and hadoop core (seems you have done), and then invoke
the command
bin/hadoop -jar hadoop-0.20.2-example.jar sort -libjars
hadoop-core-0.20.2.jar(your new builded jar)  other_arguments
PS: I do not recommend you to put your code mixed with hadoop code,
it's better to put it another places, and build an individual jar.
On Wed, Sep 8, 2010 at 1:12 AM, Matthew John <[EMAIL PROTECTED]> wrote:

Best Regards

Jeff Zhang