Microsoft push notification messages are not delivered to Lync mobile clients
Taken from Microsoft KB2664650
Microsoft push notification messages are not delivered to Lync mobile IOS and WP7 clients, when URL filtering is configured on Lync 2010 Edge Servers or office communication 2007 R2 Access Edge Server, apparently this is caused by:
Microsoft Lync 2010 Mobility Guide
This document guides you through the process of deploying the Microsoft Lync Server 2010 Mobility Service and the Microsoft Lync Server 2010 Autodiscover Service. When you deploy the Mobility Service, users can use supported iOS, Android, Windows Phone, or Nokia mobile devices to perform such activities as sending and receiving instant messages, viewing contacts, viewing presence. The Mobility Service also enables mobile devices to use some Enterprise Voice features, such as click to join a conference, Call via Work, single number reach, voice mail, and missed calls.
When you use the Microsoft Lync Server 2010 Autodiscover Service along with the Mobility Service, mobile devices can automatically locate the URLs for Lync Server Web Services and the new Mobility Service regardless of network location.
The Mobility Guide is available for download here
Boost your Lync Server 2010 with the new Mobility Service and Autodiscover Service
When you deploy the Microsoft Lync Server 2010 Mobility Service, users can use supported iPhone, iPad, Android, Windows Phone, or Nokia mobile devices to perform such activities as sending and receiving instant messages, viewing contacts, and viewing presence. In addition, mobile devices support some Enterprise Voice features, such as click to join a conference, Call via Work, single number reach, voice mail, and missed calls. By using Call via Work, users can maintain their work identity during a call, which means that the call recipient does not see the caller's mobile number, and the caller avoids incurring outbound calling charges. With single number reach, a user receives calls on a mobile phone that were dialed to their work number.
When you use the Microsoft Lync Server 2010 Autodiscover Service along with the Mobility Service, mobile devices can automatically locate the URLs for Lync Server Web Services and the new Mobility Service regardless of network location. It supports client connections using either HTTP or HTTPS.
The Mobility Service Bits are available for download here
Lync server 2010 Cumulative updates 4 November 2011 CU4 is a requirement prior deploying the Mobility Service.
Supported Mobile Clients should be released soon, the expected release date is 12-12-2011