Problem sorting Date

Hi,

I have spreadsheet includes different data in it, and there is date columne with a format Mar 11, 2007
when I try to sort it by date I get the results like this:

Mar 1, 2007
Mar 11, 2007
Mar 12, 2007
Mar 14, 2007
Mar 19, 2007
Mar 2, 2007
Mar 20, 2007
Mar 21, 2007

as you see the date of Mar 2, 2007 comes after the 19 where it should be comes after the Mar 1, 2007

can anyone tell whats wrong I'm doing in Sorting the date.?

Thank you all for your help.

Sounds like it's treating it as text as opposed to a date value.