function isDateInPast(date){
		var min = new Date();
		var max = new Date(2010,10,05);
		oneDay = 24*60*60*1000;
		
		if (date.getTime() <= min.getTime() - oneDay ||
		    date.getTime() > max.getTime())
			return true; // true says "disable"
		else
			return false; // leave other dates enabled
		
}

function isValidDate(dateStr) {
	// Checks for the following valid date formats:
	// MM/DD/YY   MM/DD/YYYY   MM-DD-YY   MM-DD-YYYY
	// Also separates date into month, day, and year variables
	
	var datePat = /^(\d{4})(\/|-)(\d{1,2})\2(\d{2}|\d{1,2})$/;
	
	// To require a 4 digit year entry, use this line instead:
	// var datePat = /^(\d{1,2})(\/|-)(\d{1,2})\2(\d{4})$/;
	
	var matchArray = dateStr.match(datePat); // is the format ok?
	if (matchArray == null) {
		alert("Датата не е във валиден формат.")
		return false;
	}
	month = matchArray[3]; // parse date into variables
	
	day = matchArray[4];
	year = matchArray[1];
	
	
	var myDate=new Date(year,month-1,day)
	if(isDateInPast(myDate)){
			alert('Избраната дата е дата в миналото');
			return false;
	}
	

	if (month < 1 || month > 12) { // check month range
		//alert("Month must be between 1 and 12.");
		return false;
	}
	
	if (day < 1 || day > 31) {
		//alert("Day must be between 1 and 31.");
		return false;
	}
	if ((month==4 || month==6 || month==9 || month==11) && day==31) {
		//alert("Month "+month+" doesn't have 31 days!")
		return false
	}
	if (month == 2) { // check for february 29th
	var isleap = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
	if (day>29 || (day==29 && !isleap)) {
		alert("Февруари " + year + " няма " + day + " дни!");
		return false;
	   }
	}
	return true;  // date is valid
}