How to add a pull down date to the Custom User Profile Field?

[93Corvette]

How do you add a pull down date to the User Custom Profile Field?
https://vborg.vbsupport.ru/external/2011/11/57.jpg

I know I could just enter "Date:" But I'd have people doing it all different ways like:
11 December 2011
11 Dec 2011
11 Dec 11
2011 Dec 11
2011 December 2011
12/11/2011
12/11/11
11/12/2011 (Europe)

I just want the guys to use a set way of doing this will a "pull down"...
Thanks