Hi Guys,

i have a registration form and i have added a terms and conditions checkbox on it.
If a user trys to register without accepting terms and conditions a pop up should appear letting them know they need to check the box to continue
This works fine in firefox
In IE nothing happens when i click the submit button, i don't get any error, even if the checkbox is ticked still nothing happens when the submit button is pressed

I dont have a direct link to the form but this is the code that is causing the issue

Code:
<script type="text/javascript">
window.onload=function(){
document.forms[0].onsubmit=function(){
   return checkIt();
  }
 }

function checkIt() {
if(document.getElementById('tos').checked==false) {
   alert('you need to check the "I accept terms of service" box');
   document.getElementById('tos').className='highlight'
   return false;
  }
else {
   document.getElementById('tos').className='';
   return true;
  }
 }
</script>
HTML Code:
<FORM ACTION="" NAME="CorpForm" METHOD="post">
 
      </TABLE></TD></TR></TABLE><BR><BR>
      <TABLE BORDER="0" CELLPADDING="1" CELLSPACING="0" WIDTH="100%"><TR><TD CLASS="maindarker" ALIGN="left">&nbsp;&nbsp;Login Information
      <TABLE BORDER="0" CELLPADDING="4" CELLSPACING="0" WIDTH="100%">
<TR><TD CLASS="mainlightest" COLSPAN="2"> Please enter below a username and a password of your choice. </TD></TR>
      <TR>
        <TD CLASS="mainlightest" >Username *</TD><TD CLASS="mainlightest" ><INPUT TYPE="TEXT" NAME="username" value="USERNAME" /></TD></TR>

      <TR>
        <TD CLASS="mainlightest" >Password *</TD><TD CLASS="mainlightest" ><INPUT TYPE="PASSWORD" NAME="password" /></TD></TR>

      <TR>
        <TD CLASS="mainlightest" >Confirm Password *</TD><TD CLASS="mainlightest" ><INPUT TYPE="PASSWORD" NAME="password_confirm" /></TD></TR>
<TR><TD>##TERMS##</TD></TR>
    </TABLE></TD></TR></TABLE>
    <INPUT TYPE="hidden" NAME="submitted" VALUE="true" />
    <input type="hidden" name="scheck" value="" />
    <P ALIGN="right"><INPUT TYPE="Image" NAME="SUBMIT" VALUE="NEXT" SRC="/images/submit.png" ALT="NEXT" /></P>

  </FORM>
PHP Code:
$terms '<form method="post" action="checkIt();">
<input id="tos" type="checkbox"><label for="tos"> I accept terms of service</label>
</form><br><a id="displayText" href="javascript:toggle();">click here to view terms and conditions</a>
<div id="toggleText" style="display: none">
<p>here are the terms and conditions</p>
</div>'
;


$content preg_replace('/##TERMS##/'$terms$content); 
does anyone know what i am doing wrong

any help is appreciated

thanks