dataTable, Order By date Help plis!

Good Day for all,
(developing a system based on PHP and ZendFramework)

I'm here to ask for help the you, I have a "problem" in my dataTable, which is the following, I need listing by date one column, ie;

01/02/2013,

02/02/2013,

03/02/2013

Unfortunately, my dataTable is listing per day practically, it lists all the first day, then all two days, after all 3 days and so forth, example;


01/02/2013,

01/03/2013,

01/04/2013,

01/05/2013,

02/02/2013,

02/03/2013,

02/04/2013,

02/05/2013

Even when you can not see a solution.
I'm need help in question,
plis if someone have knowing, post for me plis.

Can anyone explain to me why she is doing the search this way?
or has a solution in mind that can help me.

Sorry, inglish not fluent language.
Thank you in the attention you got to look at this post.