libace-xtreactor5.4.7c2a 5.4.7-9build1 (amd64 binary) in ubuntu feisty

 Recognizing the need to write reactor-based GUI applications, the ACE
 community has created several reactor extensions for use with X Window
 System. Each of these extends the ACE_Select_Reactor to work with a
 specific toolkit. By using these reactors, your GUI application can remain
 single threaded yet still respond to both GUI events, such as button presses,
 any your own application events.
 .
 The ACE_XtReactor extends both the ACE_Select_Reactor and the X Toolkit library
 function XtWaitForMultipleEvents().