Hi all,
I have small bbcode script that works perfectly in IE. but in mozilla it doesn't work
here is script

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN"
    "http://www.w3.org/TR/html4/strict.dtd"
    >
<html>
<head>
    <head>
<!-- ... -->
<script language="JavaScript" type="text/javascript">
var v=2;
<!--
function createTag(tagId,areaId) {
 //   var x=tagId;
	
   
   var txtArea = document.getElementById(areaId);
	var aSelection = document.selection.createRange().text;
	var range = txtArea.createTextRange();


		if(aSelection) {
			// Add tags around selection
			document.selection.createRange().text = '['+tagId+']' + aSelection + '[/'+tagId+']';
			txtArea.focus();
			range.move('textedit');
			//range.select();
		}
                
		else {
			//var oldStringLength = range.text.length + '['+tagId+']'.length;
                        if(v==2){
			txtArea.value += '['+tagId+']';
			//txtArea.value += '[/'+tagId+']';
                        v=1;
                        }
                        else {
                            txtArea.value += '[/'+tagId+']';
                            v=2;
                        }
			txtArea.focus();
			range.move('character',oldStringLength);
			range.collapse(false);
			//range.select();
		}
	if ((txtArea.selectionStart) || (txtArea.selectionStart == '0')) {
            
            var startPos = txtArea.selectionStart;

        var endPos = txtArea.selectionEnd;

        txtArea.value = txtArea.value.substring(0, startPos)+'az'+ txtArea.value.substring(endPos, txtArea.value.length);


            
            return txtArea.value
            
            
        }
       
}
//-->
</script>
</head>
<body>
<!-- ... -->
	<form onSubmit="return true;">
		<textarea id="txtA" rows=20 cols=40></textarea>
	</form>
	<a href="javascript:createTag('b','txtA')"><strong>B</strong></a>
        <a href="javascript:createTag('i','txtA')"><strong>i</strong></a>
<!-- ... -->
</body>
</body>
</html>

Can anyone help me so that it works both in IE and Mozilla Firefox
Thanks for advance

check if FF suports the textRange method first,
if not,
see if FF provides an alternative method/syntax
than substitute your existing code where necessary.