My XCode (was 2.0 now 2.1, same problem) has (spontaneously?) developed a problem where when I double click a file (or use open, or...) it won't ever open a second window, but just reuses the one open window. I have tried looking for an appropriate preference, reinstalling, deleting com.apple.xcode... all to no avail. Help! (I'm running 10.4.2)