function check_date(field){
	var checkstr = "0123456789";
	var DateField = field;
	var Datevalue = "";
	var DateTemp = "";
	var seperator = "/";
	var day;
	var month;
	var year;
	var leap = 0;
	var err = 0;
	var i;
	var J;
	err = 0;
   	DateValue = DateField.value;
   	/* Delete all chars except 0..9 */   
   	month =DateValue.substr(0,1);
  	i = 1;
   	if  (checkstr.indexOf(DateValue.substr(i,1)) >= 0) 
     	{
      		month = month + DateValue.substr(i,1);
      		i = i + 1;
     	} 
   	else
     	{
      		month = "0" + month;
      
     	}     
   	if (checkstr.indexOf(DateValue.substr(i,1)) < 0) 
	{
     		i = i + 1;
   	}  
   	day = DateValue.substr(i,1);
   	i = i + 1;
   	if (checkstr.indexOf(DateValue.substr(i,1)) >= 0) 
     	{
      		day = day + DateValue.substr(i,1);
      		i = i + 1;
     	} 
   	else
     	{
       		day = "0" + day;
     	}  
   	if (checkstr.indexOf(DateValue.substr(i,1)) < 0) {
     		i = i + 1;
   	}  
        j = DateValue.length - i;
   	year =  DateValue.substr(i,j);
  	DateTemp = month + day + year;
   	DateValue = DateTemp;
   	/* Always change date to 8 digits - string*/
   	/* if year is entered as 2-digit / always assume 20xx */
   	if (DateValue.length == 6) 
	{
      		DateValue = DateValue.substr(0,4) + '20' + DateValue.substr(4,2); 
	}
   	if (DateValue.length != 8) 
	{
      		err = 19;
	}
   	/* year is wrong if year = 0000 */
   	year = DateValue.substr(4,4);
        if (year == 0) 
	{
      		err = 20;
   	}
   	/* Validation of month*/
   	if ((month < 1) || (month > 12)) 
	{
      		err = 21;
	}
   	/* Validation of day*/ 
   	if (day < 1) 
	{
     		err = 22;
   	}
   	/* Validation leap-year / february / day */
   	if ((year % 4 == 0) || (year % 100 == 0) || (year % 400 == 0)) 
	{
      		leap = 1;
   	}
   	if ((month == 2) && (leap == 1) && (day > 29)) 
	{
      		err = 23;
   	}
   	if ((month == 2) && (leap != 1) && (day > 28)) 
	{
      		err = 24;
   	}
   	/* Validation of other months */
   	if ((day > 31) && ((month == "01") || (month == "03") || (month == "05") || (month == "07") || (month == "08") || (month == "10") || (month == "12"))) 
	{
      		err = 25;
   	}
   	if ((day > 30) && ((month == "04") || (month == "06") || (month == "09") || (month == "11"))) 
	{
      		err = 26;
   	}
   	/* if 00 ist entered, no error, deleting the entry */
   	if ((day == 0) && (month == 0) && (year == 00)) 
	{
      		err = 0; day = ""; month = ""; year = ""; seperator = "";
   	}
   	/* if no error, write the completed date to Input-Field (e.g. 13.12.2001) */
   	if (err == 0) 
	{
      		DateField.value = month + seperator + day + seperator + year;
   	}
   	/* Error-message if err != 0 */
   	else 
	{
      		alert("Date is incorrect!");
      		DateField.select();
	  	DateField.focus();
   	}
}

	

String.prototype.trim = function() { return this.replace(/^\s+|\s+$/, ''); };
    
function checkisnumeric(field)
{

} 


	
 function IsNumeric(sText) 
    { 
        var validChar="0123456789"; 
        var isNumber=true; 
        var char; 
        for(i=0;i<=sText.length && isNumber==true;i++) 
           { 
        	char=sText.charAt(i); 
        	if(validChar.indexOf(char) == -1) 
        	{ 
        		isNumber = false; 
        	} 
           }
        return isNumber; 
    }