Server.CreateObject and PWS vs IIS

Hi,
I have an ASP page that creates an Automation object for communicating to our main computer. When the page is run on PWS, a seperate instance of the object is created for each user which is what I want.
But when running under IIS, a single instance of the object is created in the system context and all users share this one object. When one user is accessing this object, all other users have to wait.
Questions:
Why? What does PWS do that IIS doesn't?

I've tried setting the isolated process in IIS and using Session objects to no avail.

Thanks,
Al.

How is the component's instancing property set?

I believe it is a single instance object because through VB only one instance is created when I try to create multiple instances. But it seems like through PWS, each user gets their own single instance of this object.
I'm wondering if MTS might be an answer but I know very little about this.

Thanks for the response.
Al.