Why doesn't a toolbar show up at the bottom of an iPhone screen?

Question

I have a View XIB file that contains just a TableView and a Toolbar that I created in Interface Builder.

View - W:320 H:372  
  TableView - W:320 H:328 X:160 Y:0  
  Toolbar - W:320 H:44 X:160 Y:328

I have not changed any of the default settings in the Inspector windows. I am not doing anything in code to manipulate the two screen elements except populate the TableView with some items.

When I run the application on both the simulator and the device, the Toolbar is nowhere to be seen and the TableView takes up the entire view.

I've compared this XIB file with a 2nd XIB file which has the same layout as the first but the toolbar on that screen shows up. (The only difference is that the TableView in the 2nd XIB file is not being populated with data at this time.)

Has anyone ever encountered a situation like this before?

Any suggestions as to what to look for would be appreciated. Let me know if you need more information, etc.

Thanks in advance.

Update - 10.06.09

When I add data to the TableView in the 2nd XIB file, the toolbar at the bottom of the screen disappears. Obviously there is some relationship there though I haven't figured it out yet.