Working with Calander giving problem

Question

Hi
In a form I want to have a calander. When the application runs the calander is displayed. Here I will select a date and upon selecting the date I will perform some operation. But my problem is the calander is not allowing me to move forward or backward. I mean when the  calander is displayed it shows the current month and current date(June month 13th(saturday) ), but when I click the '>' or '<' button to select a date in July or August or May it is taking the current month's current date i.e., 13 there by not allowing me to select the date I wanted. How to overcome this
 
thanks