JavaScript not working in Firefox
<p>Hi ' im having a problem with my script in firefox, i'm getting the fault , " window.event is undefined " , where seems to be the problem? </p>

<pre><code>&lt;script language="JavaScript1.2"&gt; 

function formattel(){

 var value = document.formkkush.telefoon.value; 
 var valueLen = document.formkkush.telefoon.value.length; 

 if(valueLen&gt;2 &amp;&amp; valueLen&lt;4) 
 { 
 if(window.event.keyCode==8) 
 document.formkkush.telefoon.value=document.formkkush.telefoon.value.remove(valueLen-1,1); 
 else 
 document.formkkush.telefoon.value=document.formkkush.telefoon.value+"/"; 
 }
 if(valueLen&gt;5 &amp;&amp; valueLen&lt;7) 
 { 
 if(window.event.keyCode==8) 
 document.formkkush.telefoon.value=document.formkkush.telefoon.value.remove(valueLen-1,1); 
 else 
 document.formkkush.telefoon.value=document.formkkush.telefoon.value+"."; 
 }
 if(valueLen&gt;8 &amp;&amp; valueLen&lt;10) 
 { 
 if(window.event.keyCode==8) 
 document.formkkush.telefoon.value=document.formkkush.telefoon.value.remove(valueLen-1,1); 
 else 
 document.formkkush.telefoon.value=document.formkkush.telefoon.value+"."; 
 }
} 
</code></pre>
