Vim 7.3 - View Previous Commands and Searches

I am using Vim 7.3 on Windows Vista. The following scenario worked in Vim 7.2, but does not work in Vim 7.3:
 
While editing a file, I enter the following command - :s/a/b/
I then enter a colon (:) and press the up and down arrows to view and select any previous commands I have entered.
 
While editing a file, I enter the following search - /abc
I then enter a slash (/) and press the up and down arrows to view and select any previous searches I have entered.
 
What option(s) must be set to restore the ability to view previous commands and searches?
 
Thanks,
Roy