function blank_year( year )
{
	if( year.value == "YYYY" )
	{
		year.value = "";
	}
}
function blank_month( month )
{
	if( month.value == "MM" )
	{
		month.value = "";
	}
}
function blank_day( day )
{
	if( day.value == "DD" )
	{
		day.value = "";
	}
}
function checkyear( year )
{
	yr = parseInt( year.value, 10 );
	if( isNaN( yr ) == true )
	{
		alert("You must supply a four digit year." );
		return false;
	}
	if( year.value == "" )
	{
		alert("You must supply a year." );
		return false;
	}
	else if ( (yr < 100) && (yr > 50) )
		year.value = "19" + year.value;
	else if ( (yr < 100) && (yr <= 50) )
		year.value = "20" + year.value;
	return true;
}
function checkmonth( month )
{
	if( month.value == "" )
	{
		alert("You must supply a month." );
		return false;
	}
	mon = parseInt( month.value, 10 );
	if( isNaN( mon ) == true )
	{
		alert("You must supply a two digit month." );
		return false;
	}
	if ( (mon < 1) || (mon > 12) )
	{
		alert("The month must be between 1 and 12." );
		return false;
	}
	if( month.value.length == 1 )
	{
		month.value = "0" + month.value;
	}
	return true;
}
function checkday( day )
{
	dy = parseInt( day.value, 10 );
	if( isNaN( dy ) == true )
	{
		alert("You must supply a two digit day." );
		return false;
	}
	if( day.value == "" )
	{
		alert("You must supply a day." );
		return false;
	}
	else if ( (dy < 1) || (dy > 31) )
	{
		alert("The day must be between 1 and 31." );
		return false;
	}
	if( day.value.length == 1 )
		day.value = "0" + day.value;
	return true;
}
function checkjday( day )
{
	dy = parseInt( day.value, 10 );
	if( isNaN( dy ) == true )
	{
		alert("You must supply a three digit day." );
		return false;
	}
	if( day.value == "" )
	{
		alert("You must supply a day." );
		return false;
	}
	else if ( (dy < 1) || (dy > 366) )
	{
		alert("The day must be between 1 and 366." );
		return false;
	}

	if( day.value.length == 1 )
	{
		day.value = "00" + day.value;
	}
	else if( day.value.length == 2 )
	{
		day.value = "0" + day.value;
	}

	return true;
}


function checkstartmonth( month )
{
	if( month.value == "" || month.value == "MM")
	{
		month.value = "01";
		//alert("You must supply a month." );
		return true;
	}
	mon = parseInt( month.value, 10 );
	if( isNaN( mon ) == true )
	{
		alert("You must supply a two digit month." );
		return false;
	}
	else if ( (mon < 1) || (mon > 12) )
	{
		alert("The month must be between 1 and 12." );
		return false;
	}
	if( month.value.length == 1 )
	{
		month.value = "0" + month.value;
	}
	return true;
}
function checkstartday( day )
{

	if( day.value == "" || day.value == "DD")
	{
		day.value = "01";
		//alert("You must supply a day." );
		return true;
	}
	dy = parseInt( day.value, 10 );
	if( isNaN( dy ) == true )
	{
		alert("You must supply a two digit day." );
		return false;
	}
	if( day.value == "" )
	{
		day.value = "01";
		//alert("You must supply a day." );
		return false;
	}
	else if ( (dy < 1) || (dy > 31) )
	{
		alert("The day must be between 1 and 31." );
		return false;
	}
	if( day.value.length == 1 )
		day.value = "0" + day.value;
	return true;
}
function checkendmonth( month )
{
	if( month.value == "" || month.value == "MM")
	{
		month.value = "12";
		//alert("You must supply a month." );
		return true;
	}
	mon = parseInt( month.value, 10 );
	if( isNaN( mon ) == true )
	{
		alert("You must supply a two digit month." );
		return false;
	}
	if ( (mon < 1) || (mon > 12) )
	{
		alert("The month must be between 1 and 12." );
		return false;
	}
	if( month.value.length == 1 )
	{
		month.value = "0" + month.value;
	}
	return true;
}
function checkendday( day )
{
	if( day.value == "" || day.value == "DD")
	{
		day.value = "31";
		//alert("You must supply a day." );
		return true;
	}
	dy = parseInt( day.value, 10 );
	if( isNaN( dy ) == true )
	{
		alert("You must supply a two digit day." );
		return false;
	}
	if( day.value == "" )
	{
		day.value = "01";
		//alert("You must supply a day." );
		return false;
	}
	else if ( (dy < 1) || (dy > 31) )
	{
		alert("The day must be between 1 and 31." );
		return false;
	}
	if( day.value.length == 1 )
		day.value = "0" + day.value;
	return true;
}