QMAKE problem with incorrect caching of application icon on Mac

OS X 10.4 (tiger) caches the icons of app folders, this can result in the wrong icon being displayed for an app bundle created by Qt.

The following line needs to be added by qmake to the end of the
Makefile sequence of steps in order to guarantee that the built
application's custom icon is shown in the Finder and that the
"circle-and-slash" overlay badge is removed...

SetFile -a C TheApplication.app
or...
touch TheApplication.app

It is possible to do this by hand now, but this should be integrated into future
Qt builds.

SetFile is in the Xcode folder hierarchy and will only be installed if
Xcode has been installed. However, it can be copied to and run on a
machine where Xcode has not been installed.

The problem is that the very first step in the Makefile is to create the
folder:

TheApplication.app/Contents

*IF* the project folder is open in the Finder, it will be given a
generic icon plus a circle-and-slash overlay to indicate that (A) there
is no custom icon, and (B) this is an empty shell of an app bundle. The
finder caches this icon, so even though the Info.plist and icns files
are subsequently copied into the bundle by Makefile, the Finder will
still use the cached (incorrect) icon... until SetFile (or touch) tells
it to look again for the proper custom icon.