Hi Amit,
There is a shared video from the avayamentor regarding How to configure and use Internet Messaging on CMM. Below is the link:
http://www.youtube.com/watch?v=G3s4Oe6bDko
If you configure it like above. You are configuring your outlook to pull the message from CMM. But you cannot have your CMM to push the messages automatically to your client. As what you have mentioned there is s some 3rd party software that may do that. You might try to look at the software called mutare but this will involve some cost amount of money for integration
Hope this Helps