How to add new items in WebCatItemPage?

hi,

My requirement is to modify "GetItemPageAction" to "ZGetItemPageAction".

in that i have to modify "myItemList".

so what i have done it i had created new Z_myItemList.

now if i add any item to this,i am getting some error.

z_item = (WebCatItem) myItemList.getItem(z_i);

z_myItemList.addItem(z_item);(on this line i am getting error).

if i put comment on above line everythign is working fine.

Regards,

jayesh talreja