Running x86 XBAP applications in Win7 x64

Dear Experts-Exchange:

I have an x86 XBAP application that I am debugging in Windows 7 x64.  

If I double click on the XBAP file this will use the PresentationHost.exe version from SysWOW64, but if I try to load the same application from http://localhost/myapp/myapp.xbap I notice that (beside the error I get) the version of the PresentationHost.exe that gets loaded, is the one from C:\Windows\System32\PresentationHost.exe instead of the one from C:\Windows\SysWOW64\PresentationHost.exe.  Is there a way that I can change the default PresentationHost.exe to be loaded?  I will appreciate your feedback.

Best regards,

Conrado