c:catch error

[Brian Hart <BH...@mail.nysed.gov>]

I have a predictable sequence of events that cause an recoverable
exceptional condition when working with c:catch and c:import.
Here is the scenario:
 
1.  First time ContentManager.contentURL contains an unknown file such
"notarealfile.htm"
<c:catch var="exceptions">
   <c:import url="${ContentManager.contentURL}" /> 
</c:catch>
<c:if test="${exceptions != null}" >
  <c:import url=""/errors/500error.html" " /> 
</c:if>
 
I receive a FileNotFound Exception which is good.  The full exception
is:
javax.servlet.jsp.JspException: Problem accessing the absolute URL
"http://localhost:8988/vls/published/faq/Arts_771.htm".
java.io.FileNotFoundException:
http://localhost:8988/vls/published/faq/Arts_771.htm 
 at
org.apache.taglibs.standard.tag.common.core.ImportSupport.acquireReader(ImportSupport.java:372)
 at
org.apache.taglibs.standard.tag.common.core.ImportSupport.acquireString(ImportSupport.java:259)
 at
org.apache.taglibs.standard.tag.common.core.ImportSupport.doEndTag(ImportSupport.java:179)
 at _main._jspService(main.jsp:27)

 
2.  On the subsequent requests for the page  with
ContentManager.contentURL now containing a valid file such as
'realfile.htm' I receive a 
Classcast exception.  If I remove the <c:catch> wrapper this condition
goes away.  The exeption still occurs but it 'gracefully' recovers when
then passed a valid url.  but with the c:catch I'm forever stuck in the
ClassCastException regardless of the URL passed.
 
Any information or suggestions would be greatly appreciated.
 
Thanks,
Brian