I need help regarding the validation of the form using javascript

I am using this function to validate my form.....I am able to validate all the fields except radio buttons, I am not able to figure it out whats the problem with the function.
how do i make it so that it validates the radio buttons too
here is the code.....

<script type="text/javascript">


var strAlertMsg = ""
var focusField = ""
//Validate Radio Button
function checkRadioControl(theForm,strFieldName,strMsg){
var objFormField = theForm.elements[strFieldName]
intControlLength = objFormField.length
bolSelected = false;
for (i=0;i<intControlLength;i++){
if(objFormField[i].checked){
bolSelected = true;
break;
}
}
if(! bolSelected){
strAlertMsg += "- "+ strMsg +" is Required.\n";
return false;
}
return true;
}


//Begin Page Validation
function validateForm(theForm){
strAlertMsg = ""
focusField = ""
  checkRadioControl(theForm,'radio1','What Kind of Issue do you have')
    
if(strAlertMsg !=""){
alert("Please correct the following errors:\n____________________________\n\n" + strAlertMsg);
eval("theForm." + focusField + ".focus()");
return false;
}
return true;
} 
 
 
</script>

<form id="form1" action="new5.asp" method="post" onsubmit="return validateForm(this);">
<tr>
<td colspan="2"><div align="left"> <b><label id="lblRadio" for="radio1">What Kind of Issue do you have?:</label></b> <em>*</em> </div></td>
</tr>
<tr>
<td><input type="radio" id="radio1" name="radio1" value="01" /> Problem/Question

  </td>
<td><input type="radio" name="radio1" value="02" />Comment </td>
</tr>
</form>


Thanks