Causes Validation Issue In Windows Application

I have two textbox  and two button on form such as Ok and Cancel.

and i write textbox validating & validation event which is working well when i presses ok button . 

But In case of cancel button i Set the causesvalidation Property of cancel button is False.

After that when i press Cancel Button it also Fire the Textbox Validating Event.

wherever as per MSDN it will be suppressed. But it not?

any idea about that?

i am using Visual Studio .Net 2008 If it make any issue.

Gaurav Srivastava