I just installed Qt 4.5.1 and the VS add-in. In Visual Studio, when I go to Qt>Open Qt Project File, the add-in output looks like this:

--- (Import): Generating new project of tpsdkdialogsx_qt.pro file
...
--- (qmake) : Arguments: -spec $(QTDIR)\mkspecs\win32-msvc2005 -tp vc "tpsdkdialogsx_qt.pro" -o "tpsdkdialogsx_qt.vcproj" QMAKE_INCDIR_QT=$(QTDIR)\include QMAKE_LIBDIR_QT= QMAKE_LIBDIR=$(QTDIR)\lib QMAKE_UIC=_(QTDIR)\bin\uic.exe QMAKE_MOC=_(QTDIR)\bin\moc.exe QMAKE_RCC=_(QTDIR)\bin\rcc.exe QMAKE_QMAKE=$(QTDIR)\bin\qmake.exe

Notice the use of $(QTDIR) in some places and _(QTDIR) in others. When I build, I get an error like this:
Qt Code: 
  1. 1>'_' is not recognized as an internal or external command
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If I open the vcproj file in a text editor and replace all instances of _(QTDIR) with $(QTDIR), the project builds as I expect.

Does any one know what's going wrong?