multiple group of radio buttons validation

hi guys, i have a form with input text, dropdown menu and groups of radio button. the validation for input text and dropdown menu works fine with these js validator -

<script language="JavaScript">
function formValidator(){

// Make quick references to our fields

 var pensyarah = document.getElementById('pensyarah');
 var kksem = document.getElementById('kksem');



 // Check each input in the order that it appears in the form!
if(madeSelection(pensyarah, "Sila pilih Pensyarah")){
 if(madeSelection(kksem, "Sila pilih Kod kursus")){



 return true;
 }
 }


 return false;

}



function isEmpty(elem, helperMsg){
 if(elem.value.length == 0){
  alert(helperMsg);
  elem.focus(); // set the focus to this input
  return true;
 }
 return false;
}

function isNumeric(elem, helperMsg){
 var numericExpression = /^[0-9\s\:]+$/;
 if(elem.value.match(numericExpression)){
  return true;
 }else{
  alert(helperMsg);
  elem.focus();
  return false;
 }
}

function isAlphabet(elem, helperMsg){
 var alphaExp = /^[a-zA-Z\s\.]+$/;
 if(elem.value.match(alphaExp)){
  return true;
 }else{
  alert(helperMsg);
  elem.focus();
  return false;
 }
}

function isAlphanumeric(elem, helperMsg){
 var alphaExp = /^[0-9a-zA-Z\s]+$/;
 if(elem.value.match(alphaExp)){
  return true;
 }else{
  alert(helperMsg);
  elem.focus();
  return false;
 }
}

function madeSelection(elem, helperMsg){
 if(elem.value == "*Tiada Pilihan"){
  alert(helperMsg);
  elem.focus();
  return false;
 }else{
  return true;
 }
}


function emailValidator(elem, helperMsg){
 var emailExp = /^[\w\-\.\+]+\@[a-zA-Z0-9\.\-]+\.[a-zA-z0-9]{2,4}$/;
 if(elem.value.match(emailExp)){
  return true;
 }else{
  alert(helperMsg);
  elem.focus();
  return false;
 }
}


</script>

my question is.. how to do the group of radio button validation inside the existing js validator.. is it posible to merge it in one function?

this is my form code:
http://www.modernessence.net/e1flashz/im...

this is how the form looks like
http://www.modernessence.net/e1flashz/im...

any ideas..

Thank you in advance.

(sorry for my english, i'm from malaysia)