function Isdate(strDate)
{	var Error = 0;
	var arrDate = strDate.split('/')
	if (arrDate.length < 3)
	{		return false
	}else
	{		var y = arrDate[2]
		var m = arrDate[1]
		var d = arrDate[0]
		if (d.length == 1)	d = '0' + d
		if (m.length == 1)	m = '0' + m
		if (y.length == 2)
		{			if (y > 49)
			{				y = '19' + y
			}else 
			{				y = '20' + y
			} 
		} 
		if (d.length != 2 || m.length != 2 || y.length != 4) return false
		//check the values
		if (isNaN(d) || d<0 || d.indexOf(',')!=-1 || d.indexOf('.')!=-1 || d.indexOf('-')!=-1) Error = 1
		if (isNaN(m) || m<0 || m.indexOf(',')!=-1 ||	m.indexOf('.')!=-1 || m.indexOf('-')!=-1) Error = 1
		if (isNaN(y) || y<0 || y.indexOf(',')!=-1 || y.indexOf('.')!=-1 || y.indexOf('-')!=-1) Error = 1
		if (m<1 || m>12) Error = 1
		if (d<1 || d>31) Error = 1
		if (y<1990 || y>2079) Error = 1
		//check months with 30 days
		if (m==4 || m==6 || m==9 || m==11)
		{			if (d==31) Error=1
		}
		// february, leap year
		if (m==2)
		{		// feb
			var feb=parseInt(y/4)
			if (isNaN(feb)) 
			{				Error=1
			}
			if (d>29) Error=1
			if (d==29 && ((y/4)!=parseInt(y/4))) Error=1
		}
		if (Error != 0) return false
	} 
	return true
}