Bug 60907 Two progress dialogs when building WS + dragging a file into the navigator
build N20040503 - start the workspace - delete a view_menu.gif file from org.eclipse.ui\icons... - note for me that a build starts now - drag another file from the file system while the build is happening - drop it on the folder where the first file was deleted from two progress dialogs appear... see attachment.
bundles/org.eclipse.jface/src/org/eclipse/jface/dialogs/IDialogBlockedHandler.java
/**
	 * The blockage has been cleared. Clear the
	 * extra information and resume.
	 */
	public void clearBlocked();
	
	/**
	 * A blockage has occured. Show the blockage and 
	 * forward any actions to blockingMonitor.
	 * @param parentShell The shell this is being sent from.
	 * @param blocking The monitor to forward to. This is most
	 * important for calls to <code>cancel()</code>.
	 * @param blockingStatus The status that describes the blockage
	 * @param blockedName The name of the locked operation.
	 */
	public void showBlocked(Shell parentShell, IProgressMonitor blocking, IStatus blockingStatus,
			String blockedName);
	
	/**
	 * A blockage has occured. Show the blockage and 
	 * forward any actions to blockingMonitor. 
	 * 
	 * @param blocking The monitor to forward to. This is most
	 * important for calls to <code>cancel()</code>.
	 * @param blockingStatus The status that describes the blockage
	 * @param blockedName The name of the locked operation.
	 */
	public void showBlocked(IProgressMonitor blocking, IStatus blockingStatus,
			String blockedName);
}