Struts can be configured for exception  handling via struts-config. It
is called "Declarative Exception Handling" .
Take a look at below url for an overall view of this feature:
javaboutique.internet.com/tutorials/excep_struts/

As you might notice, the goal is to remove exception handling  from
code to configurations classes. You just define the type of exceptions
and the class  that will go to handle them. You can configure it for
each action  too.

I have not used this feature, but seem to be very useful. This applies
to struts  1.1 but maybe new features for this in struts1.2.