Regular Expression for validating Dates

Regular expression for validating dates is:


^\s*((31([-/ ])((0?[13578])|(1[02]))\3(\d\d)?\d\d)|((([012]?[1-9])|([123]0))([-/ ])((0?[13-9])|(1[0-2]))\12(\d\d)?\d\d)|(((2[0-8])|(1[0-9])|(0?[1-9]))([-/ ])0?2\22(\d\d)?\d\d)|(29([-/ ])0?2\25(((\d\d)?(([2468][048])|([13579][26])|(0[48])))|((([02468][048])|([13579][26]))00))))\s*$