One of our apps has an in its ibm-web-ext.xmi the attribute:
When I open the web projects deployment descriptor in RAD 7.5, there
is no place to edit the value for this attribute.
Every so often, the application suffers some kind of error and tries
to forward the user to this default error page. This is a problem
because this application has no such resource named "error.jsp" and
this causes some worrying-looking stack traces. If the user tries to
refresh the page, they get the page they were trying to access and the
error goes away. At least from the user's perspective, this is an easy

What I'd like to know is why can't I edit this value in the deployment
descriptor editor GUI (I suspect this is a leftover from when the
application was originally developed on WSAD 5 or older)?

Also, is there any general class of error that would cause WebSphere
to attempt to forward to defaultErrorPage? This error is reported only
once every few months (at the most frequent, once a year at the least
frequent), and does not appear to be easily reproducable - any action
taken by the user seems capable of triggering this situation, but it
is obviously rare that it does.