[news.eclipse.platform.rcp] Part already exists in page

[nebulour@xxxxxxxxx (Brian)]

Using a configuration file, I'm trying to put perspectives on the 
Perspective Bar by executing code similar to the following.  The code on 
line #3 gives me the message on the bottom.  Any idea on what I need to 
do?  The app comes up fine but I really don't like seeing those 
error/warning messages.  I've tried checking for open perspectives but 
that didn't help.

1) IWorkbench workbench = PlatformUI.getWorkbench();
2) IPerspectiveDescriptor pDesc =
    workbench.getPerspectiveRegistry().findPerspectiveWithId(perspective);
3) 
workbench.getActiveWorkbenchWindow().getActivePage().setPerspective(pDesc);


!ENTRY org.eclipse.ui 4 4 2008-05-08 21:03:53.238
!MESSAGE Part already exists in page layout: <view id>