// JavaScript Document
function check_sales_form()
{
	check = "N";
	arCheck = $("input:checkbox").get();
	for (i=0; i<arCheck.length; i++)
	{
		if(check == "N")		
		{
			if(arCheck[i].checked)
			{
				check = "Y";
			}
		}
	}
	if(check == "Y")
	{
		return true;
	}
	else(check == "N")
	{
		$("#error_message").css(
		  {
			display: "block"
		  }
		);
		return false;
	}
	return false;
}