function validateForm(source, args) {
    var returnVal = true;
    if(document.getElementById("ctl00_bcr_ctl00_ctl00_GenderMale").checked && 
        document.getElementById("ctl00_bcr_ctl00_ctl00_GenderFemale").checked) { 
            document.getElementById("genderError").style.display = "inline"; 
            returnVal = false; 
     }else {
         document.getElementById("genderError").style.display = "none";
     }
     
     //validate birthdate
        var bmo = document.getElementById("ctl00_bcr_ctl00_ctl00_Month").value;
        bmo = bmo - 1;
        var bday = document.getElementById("ctl00_bcr_ctl00_ctl00_Day").value;
        var byr = document.getElementById("ctl00_bcr_ctl00_ctl00_Year").value;
		var age = 0;
        var now = new Date();
        tday=now.getDate();
        tmo=(now.getMonth());
        tyr=(now.getFullYear());
        if((tmo > bmo)||(tmo==bmo & tday>=bday)) { age=byr; }        
        else { age=(parseInt(byr)+1); }
        age = tyr-age;
        if(age < 13) { 
            document.getElementById("birthdateError").style.display = "inline"; 
            returnVal = false;  
        }else{
            document.getElementById("birthdateError").style.display = "none";
        }	
        
        //check terms & conditions
        if(!document.getElementById("ctl00_bcr_ctl00_ctl00_TermsConditions").checked) { 
            document.getElementById("termsError").style.display = "inline";
            returnVal = false;
        }else{
            document.getElementById("termsError").style.display = "none";
        }
    
        args.IsValid = returnVal; 
        
}