title: Mac OS X 10.5 App "not supported on this architecture" cured by copying?
body: <p>I have an app that updates itself over the internet, and the updated copy won't run on PowerPC machines (G5) running Leopard (10.5.8).  Double-clicking the app produces a message saying "You can't open the application "<em>appname</em>" because it is not supported on this architecture."  But here's the weird part:  if I duplicate the app using the Finder or using a <code>cp -R</code> command, then the duplicate runs fine!  And yet, if I do <code>ls -laeR</code> on both apps, the results are identical.  I restarted the machine, and the difference between the two copies was still there.</p>
  
  <p>Sometimes, renaming the app made it run.  After a few tries, I managed to rename it back to the original name and still have it run.</p>
  
  <p>If this was just on one machine, I'd dismiss it as disk corruption, cosmic rays, or a voodoo hex, but it was reported by a customer and then I reproduced it on my own machine.</p>
  
  <p>Any ideas what could cause this behavior?</p>