Convert string to date

I have a report that has an expiration field I want to sort by expiration but when clicked it sorts alphanumerically and shows january 01 before march 03 no matter what the year. If i do select expiration and sort it works fine but if i say select [expiration]=convert(char(10), expiration, 101) it sorts alpha numerically. I want to display in the format above but sort by date Please help