How can I set a breakpoint in .NET Framework source code using Visual Studio 2010 Express?

Question

I need to set a breakpoint in System.Web.Handlers.ScriptModule.OnPostAcquireRequestState and then step into some of the System.Web.Script.Services.WebServiceData methods.

But I only have Visual Web Developer 2010 Express (or other Express SKUs). I have configured the Microsoft Symbol Server and unchecked the Just My Code option. I can see that the symbols for System.Web.Extensions are downloaded and cached.

However, this version of Visual Studio doesn't have the breakpoints window, so I don't see a good way to set the breakpoint.

Am I just out of luck or is there another way to set a breakpoint in this method? It seems the option for the symbol server is pointless without the option to set a breakpoint.