I'm reporting this as a bug in the Infragistic's Menuing system.  It deals with displaying a popup menu over a third party control hosted by out-of-process COM server.  The bug can be seen in the following video:

http://www.youtube.com/watch?v=KvdUjOlVZzE

It deals with simply popping a menu up over the Tracker company's Viewer control.  The control is owned by an out of process COM server.  The video shows a hack to their FullDemo.EXE sample application installed with their SDK (scream if you want my hacked version to reproduce it in house).  I've reported the bug in their forum as well. 

The video shows simply hovering the mouse over the menu and having it choke.  An easier way is to simply pop up the menu and click in the Shadow of the menu, at this point the application will "freeze".  Once frozen, if the user takes an application window (say your email client or something) and covers the menu, then the froze application will respond to input again.

Doing the same exact thing with a normal Window's menu works perfect!  Again, the bug only manifests with the Infragistics menus.

I've reported to this to the Tracker group and their developer responded with:

"...when you clicks on shadow under Infragistic's context menu the client app (FullDemo.exe) will freeze.. We cannot solve this bug because it is not ours, please contact Infragistic ("Infragistic's popup menu works sometimes incorrectly when the menu is over a window from another process")..."

The link to the form post is (search for the text given above):

http://www.tracker-software.com/forum3/viewtopic.php?f=36&t=9193&p=44096#p44096

Please let me know if you need further information regarding this.  I'm running VC 2008, Windows 7, 64-bit, fully service packed, patched, hacked, blah blah.  I've reproduced the bug in version 10.3 as well as prior versions.