I have a function used on the datepicker to limit dates selected to the first of the month... I invoke it by setting a class and listener, such as:

$( ".datepickfom" ).datepicker(
    {
        beforeShowDay:  fom,
        showOn: "both",
        buttonImage: "/images/calendar.png",
        buttonImageOnly: true,
        changeMonth: true,
        changeYear: true,
        dateFormat: "m/d/yy",
        yearRange: "-25:+100",
        constrainInput: true
    }
);

the fom call:

 function fom(date){
    if (date.getDate() != 1) {
        return [false, "", "Specify 1st of Month"];
    }
    return [true, ""];
}

This works great for regular forms.

I'm looking to extend this functionality to the HandsOnTable 'date' cell data types.

var $container_1 = $("#datatable_1");
var handsontable_1 = $container_1.data('handsontable');
$("#datatable_1").handsontable(
{ columns: [
{},
{},
{
 type: 'date', 
 dateFormat: 'm/d/yy'
},
{},
{
 type: 'dropdown', 
 source: ["","Y","N"]
},
{},
{}
]
});

This also works as it should, but the date lets me pick other dates besides the first.

Is there a way to attach the

beforeShowDay

option to the HOT cell call as well?