Am pulling my hair out on this...

By scenario is kind of complex, but I have a masterpage with a radajaxmanager, then a page with multiple use controls. In one of the controls, I have a button within a radgrid that I want to generate a download request:

Response.Clear()
Response.ContentType = "Application/msword"
Response.AddHeader("content-disposition", "attachment;filename=test.xml")
Response.Write(teststring)
Response.End()

Obviously, I need to disable AJAX for this postback...
In my grid, I have a GridTemplateColumm that has a btnGenerate
On the grid's ItemDataBound:
Dim sm As ScriptManager = ScriptManager.GetCurrent(Page)
sm.RegisterPostBackControl(CType(e.Item.FindControl("btnGenerate"), LinkButton))

But no matter what I try, when the Grid's ItemCommand is raised by the button, it remains an AJAX request.

Thanks,
Reuven
(I don't want to save the generated file nor run it through a handler to generate since it contains confidential data)