So a coworker found this out if you run this test page Coldfusion will return that the cfcatch is not a struct even though when you dump the variable it says that it is a struct. Also on the argument in the function if you put a type="struct" Coldfusion will error out saying that it is not a struct. I have filed a bug here: Bug Also it turns out that it is not just a CF9 issue I have seen it as well in my local CF8 instance.
<cfargument name="exception" required="true"/>
<cfthrow message="Help!!!!" />
<cfset testFunction(exception=cfcatch) />