Call Suite should be a product from Dialogic, an Intel company. I have no experience with this product.
However, before I would try to do something as you suggested, I would find out if the library or ActiveX controls are thread safe or not.
There isn't a whole lot of information on this product, but you can find some technotes and white papers on Intel's website. Just go to www.intel.com and select developer, software development, networking and communications, communication boards & systems.