Need information on how to extend CCK widget

I created a module which adds multi-column display option to checkboxes/radios form element: http://drupal.org/project/multicolumncheckboxesradios

Someone asked to have this integrated with CCK. Is it possible to do?

It would need to have multi-column options settings for any field that uses the checkboxes/radios widget.

I think I need to somehow extend the 'optionwidgets_buttons' in optionwidgets.module.

Any pointer to how to do this is greatly appreciated!