:sh doesn't open shell window

[stri ker]

I am using version 7 on Mac OS X.  When I open a shell with :sh, Vim  
only runs a single command line at the bottom of the screen. In  
previous versions and on my Windows box the :sh command opens a new  
shell window.  In addition, the 'clear' command doesn't clear and  
redraw the screen.

How can Vim be configured to open a new window for a shell?
Can I force a clear when in shell?
TIA,
Kevin