If you want to OPEN all IM that you are receiving than it is not possible natively with the Lync CLient.
Please check: http://www.modalitysystems.com/software for Lync Super Toast ...
Hi,
Would you please tell us why you want to complete the function?
There is no way naturally to complete the function until now. Whats more, it will influence your work.
If you want this function, you may need to custom your own Lync client, you can post the question on MSDN Lync SDK forum. Thank you for your understanding.
http://social.msdn.microsoft.com/Forums/en-US/communicatorsdk/threads
Best Regards,
Eason Huang