HTML checkbox value is clear when scrolling

Hi,

I am using HTML checkbox in one of the columns in the active widget grid (not the grid checkbox) by writing the <input type=checkbox> tag in the column value.
If the user checked some of them then scrolling down and up again the checkbox loses its value.
What can I do?
I know that there are checkbox template in the grid but I already have working application with lots of grid and checkboxes.

Thanks,
Yaron