There is a hidden Duplicate Page function in CorelDRAW 11, 12 and X3:
You can select more than one page with Ctrl or Shift keys before duplicating.
CorelDRAW X3 will add empty page if you try to duplicate a page that contains a locked object.
In CorelDRAW X4, you can easily find the function under
When you duplicate a page, you can choose to only copy the layer structure of the page or you can copy the layers and all the objects they contain.