function mustCheck( name, message )
{
	if ( message.length == 0 )
	{
		alert( name + "が未入力です。" );
		return false;
	}
	return true;
}

function mailCheck1()
{
	var	check1_1 = false;
	var	check1_2 = false;
	var	check1_3 = false;
	var	check2_1 = false;
	var	check2_2 = false;
	var	check2_3 = false;
	var	check3_1 = false;
	var	check3_2 = false;
	var	check3_3 = false;
	var	check1   = false;
	var	check2   = false;
	var	check3   = false;
	var	error_message = "厚生年金、国民年金、共済年金のいずれかを入力してください。";

	check1_1 = ( document.form1.p1year1.value.length  > 0 );
	check1_2 = ( document.form1.p1month1.value.length > 0 );
	check1_3 = ( document.form1.p1day1.value.length   > 0 );
	check2_1 = ( document.form1.p2year1.value.length  > 0 );
	check2_2 = ( document.form1.p2month1.value.length > 0 );
	check2_3 = ( document.form1.p2day1.value.length   > 0 );
	check3_1 = ( document.form1.p3year1.value.length  > 0 );
	check3_2 = ( document.form1.p3month1.value.length > 0 );
	check3_3 = ( document.form1.p3day1.value.length   > 0 );

	check1 = check1_1 && check1_2 && check1_3;
	check2 = check2_1 && check2_2 && check2_3;
	check3 = check3_1 && check3_2 && check3_3;

	if ( ( check1 + check2 + check3 ) != 1 )
	{
		alert( error_message );
		return false;
	}

	if ( check1 )
	{
		if (  check1_1 &&  check1_2 &&  check1_3 &&
			 !check2_1 && !check2_2 && !check2_3 &&
			 !check3_1 && !check3_2 && !check3_3 )
		{
			return true;
		}
	}
	if ( check2 )
	{
		if (  check2_1 &&  check2_2 &&  check2_3 &&
			 !check1_1 && !check1_2 && !check1_3 &&
			 !check3_1 && !check3_2 && !check3_3 )
		{
			return true;
		}
	}
	if ( check3 )
	{
		if (  check3_1 &&  check3_2 &&  check3_3 &&
			 !check1_1 && !check1_2 && !check1_3 &&
			 !check2_1 && !check2_2 && !check2_3 )
		{
			return true;
		}
	}
	alert( error_message );
	return false;
}