Problem with checkbox

 Hi,
I am stuck with a problem for quite a long time.
I am explaining step by step
1.) Create a checkbox - set autopostback = true ; attach Checkchanged event handler.
2.) Create a buttton-> attach a javascript that changes checkbox value to true and return false so no post back
3.) Now i run website
4.) I click checkbox-> Event gets called!
5.) Now i rereun the same website
6.) Click on button. The Checkbox is checked(using JS) and no postback occurs(This is Ok)
7.) If i now unchck the checkbox manually, the event is not handled(Here the checkbox server side code is not called)
 Anyone has any ideas...
 
Thanks,
Priyan
 
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