[pdftex] filled box? (like psboxit)

[Troy Goodson]

How do I make a filled box like psboxit would do?

I want to use this to make a white box to cover up a line on an 
overlay for a header/footer.

my overlay: (a pdf file showing a big box and some graphics)
+----------------+
|                |
|                |
|                |
+----------------+

what I want:
+----------------+
|                |
|                |
|                |
+- footer -------+

I don't want the line to be visible under or around the footer.

I figure I can get this if I use a white, filled box in the footer. 
Any thoughts?