function update_contact_roles(field)
{
	$('#contact_role_id').html('');
	$('#contact_role_id').append('<option disabled="disabled" selected="selected">Select From Dropdown</option>');
	if(contractor_contacts[field.value] != undefined)
	{
		for(var i = 0; i < contractor_contacts[field.value].length; ++i)
		{
			$('#contact_role_id').append(
				'<option value="' + contractor_contacts[field.value][i]['contact_role_id'] + '">' + contractor_contacts[field.value][i]['contact_role'] + '</option>'
			);
		}
	}
}