Show text box on first page only. Then also show depending on a parameter value

Hi there,

I have 2 text boxes showing in my header on a report in visual studio 2008.    I know how to display the header only on the first page by using true and false.

=IIf(Globals!PageNumber=1,true,false, )

However I want to now only show the header depending on a parameter value as well as the first page only.  So I created the following code, and put it into the hidden formula field.

=IIf(Globals!PageNumber=1,true,false, ) and (Parameters!ClassID.Value <> 291)

It does not show an error, and runs the report.  However the text box still shows on each page of the report.  Do I need to use and IIF statement on the second part as well?