Hi,

We would like our users to receive the usual notification (flashing yellow in the taskbar) when a message is sent to a persistent chat room that they are a member of.

Changing the user's global notification settings (or their individual room notification setting) to 'Show me an alert' will show a small alert box on the user's screen, but we would much prefer the flashing yellow notification that we receive with normal messages.  

Is this possible?

Hi,

It is by design and can't be changed naturally.

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