Report paging

I have a SSRS reportviewer on an aspx page. The report works fine. If I print it it has 6 pages.

But on the screen it show all rows and the paging control shows 1 of 1.

How can I get the report to to do paging on the screen? Especially if I have thousands of rows of data.

Thanks

 It works in ASP.NET 4.5 perfectly but not in ASP.NET 3.5. Interesting...