asp.net: calling asp page while wcf operation is processing

Question

I have a web application consists of several aspx pages + wcf service (one project) and a silverlight app. I have the following problem: I open silverlight app, it does async call to my long wcf service operation. While it is processing I can't request any other aspx page of my site. Why it happens? Is it session locking? I will be grateful for the tip. I can get any non asp page from server (iis6), but any aspx page can be processed only after wcf operation is done.

EDIT: I solved it by

aspNetCompatibilityEnabled="false"

Answer 1

Maybe your wcf ws is locking a database table also used by other aspx pages. Are you using synchronization locks ? Serializable transactions ? Or maybe you have a debugger attached.