jQuery Grid Plugin - jqGrid

Hi,

I have a normal grid, filled with database data. In edit mode. This grid has 4 col. : name, firstoption,secondoption,text.

name is a name. firstoption and secondoption are two select, and text is a normal textbox.

In edit mode, i have so one textbox, 2 select and another textbox.

I want to insert option dinamically in the 2 select, in this way: when i click the 'edit' button, a function insert data in the firstselect from a database (already done function).Then, using the value of firstoption, i want to insert data dinamically in secondoption. Here i found a problem, because i need a 'onchange' event on the choosen select (in this case, when the value of firstoption changes, a function would fire, adding options to secondoption)

So, is possible in the colModel declaration to assign a 'onchange' event to 'firstoption' when it is in edit mode? I've read something in the 'editoption' parameter, but i don't know the sintax

thanks, Salvo