Here is a way to disable specific dates from being selected:
var unavailableDates = ["9-5-2011","14-5-2011","15-5-2011"];
function unavailable(date) {
dmy = date.getDate() + "-" + (date.getMonth()+1) + "-" + date.getFullYear();
if ($.inArray(dmy, unavailableDates) < 0) {
return [true,"","Book Now"];
} else {
return [false,"","Booked Out"];
}
}
$('#iDate').datepicker({ beforeShowDay: unavailable });
Source: jQuery – Datepicker – Disable Specific Dates