click to enlarge is not working in oscommerece

Question

Hi,

I am using oscommerece. i m trying to customize this,but in product info page there is option for click to enlarge.its not working.i saw the javascript for popup .function name was popupWindow and passing variable is url.but this function has not called from the code.that is the actual problem.

Please help me what modification is needed here or there is any other way to solve it,keep it remember i m using oscommerece version2.2rc2a....

Please help me asap

Thanks Manish