Thanks to Koen Zoomers for finding this one …

http://social.technet.microsoft.com/Forums/en-US/sharepoint2010setup/thread/d1e58832-391b-42ba-a21b-6ef40d1c9acb

<browserCaps>
  <result type="System.Web.Mobile.MobileCapabilities, System.Web.Mobile, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a"/>
  <filter>isMobileDevice=false</filter>
</browserCaps>

Open the “web.config” file for the Web Application you want to modify and insert the above code just before </system.web>.   Note:  This will disable for that one Web Application only.  For a more global solution take a look at the “compat.browser” file and instructions at http://blogs.inetium.com/blogs/bcaauwe/archive/2010/06/28/disable-mobility-features-for-sharepoint-2010.aspx