I've done this with Eclipse/Tomcat but not with Websphere. Look into JPDA.
Do a Yahoo! search on JPDA and Eclipse and you should find what you need.
A quick search brought up these pages:
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Sent by: "Web Enabling the AS400 / iSeries"
2010-03-09 14:26 [WEB400] Remote Debug jsp from
Please respond to
Web Enabling the
AS400 / iSeries
Is there a way to do remote debug on jsp that is installed on a
websphere app server?
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