Telerik reporting - fields in report header not refreshing

I have a report that has a ReportHeader section that has a couple of fields that I set in code - that aren't populated from a DataSource.

That is, in the designer I put aTextBox in the ReportHeader section, and leave it's value blank.

I'm displaying the report on a web page, using the standard Telerik ReportViewer. The Website is not running with InProc session.

I set the value in onNeed开发者_JS百科DataSource() to a value I extract from Session[]. (We simply can't run production websites with InProc session state, so these values and the parameters for the queries that populate the DataSources are passed through Session[].)

The report runs fine. The fields populate correctly, the detail section populates correctly, and the tables in the ReportFooter that have separate DataSources populate correctly.

But when I print, the fields that are set in code are blank. Same if I export, or even if I simply hit the refresh button in the ReportViewer.

The fields that are being populated from DataSources are set correctly, these fields that are populated directly are left blank. When I put a breakpoint in onNeedDataSource(), I see that it is not called, when the report refreshes. It's like the report is working from remembered data, and that the only data it remembers is what is in a DataSource.

Any ideas as to how I can make this work? Without going to InProc session state - that's simply not a workable solution.