How do I capture a ScriptTimeOut in C#?

[Mudpie]

I have a section of my online application where users can select columns and
criteria to build a report. For the page that then builds this report, I have
set the ScriptTimeOut for 8 minutes at the top of my PageLoad method.
Occasionally with a very large report the page has to do so much processing
of the data that it times out. Is it possible to capture a Script Timeout
event(?) and display a message telling my users to build that the report is
too large?