FireFox and Flash

How do I get alternative content there is no Flash plug-in

[The Cricketer]

I haven't downloaded the Flash player plug-in for Mozilla, but I would like users of FireFox who also do not have the plug-in to be able to see alternative content where the .swf should be - such as an image being displayed like there is for other browsers in the example below. For some reason the code below doesn't work in FireFox, all that appears is a blank space.

Can anyone suggest a solution?

<script language="javascript">
<!--
var ShockMode = 0;
if (navigator.mimeTypes && navigator.mimeTypes["application/x-shockwave-flash"]&& navigator.mimeTypes["application/x-shockwave-flash"].enabledPlugin){
if (navigator.plugins){
if (navigator.plugins["Shockwave Flash 3.0"] ¦¦ navigator.plugins["Shockwave Flash"]){
var isVersion2 = navigator.plugins["Shockwave Flash 3.0"]? " 3.0" : "";
var flashDescription = navigator.plugins["Shockwave Flash" + isVersion2].description;
var flashVersion = parseInt(flashDescription.charAt(flashDescription.indexOf(".") - 1));
if (parseInt(flashDescription.charAt(flashDescription.indexOf(".") - 1)) >= 4) { ShockMode=1;}
}
}
 
} else if (navigator.userAgent && navigator.userAgent.indexOf("MSIE")>=0 && (navigator.userAgent.indexOf("Windows 95")>=0 ¦¦ navigator.userAgent.indexOf("Windows 98")>=0 ¦¦ navigator.userAgent.indexOf("Windows NT")>=0 )){
 document.write('<SCRIPT LANGUAGE=VBScript\> \n');
 document.write('on error resume next \n');
 document.write('ShockMode = (IsObject(CreateObject("ShockwaveFlash.ShockwaveFlash.3")))\n');
 document.write('</SCRIPT\> \n');
} if (ShockMode) {
 document.write('<object classid="clsid:D27CDB6E-AE6D-11cf-96B8-444553540000"');
 document.write('codebase="http://download.macromedia.com/pub/shockwave/cabs/flash/swflash.cab#version=3,0,0,0" width=269 height=130>');
 document.write('<param name=movie value="http://www.mysite.co.uk/newsticker.swf">');
 document.write('<param name=quality value=high>');
 document.write('<param name=bgcolor value=#ffffff>');
 document.write('<embed src="http://www.mysite.co.uk/newsticker.swf" width="269" height="130" quality="high" type="application/x-shockwave-flash" pluginspage="http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_Version=ShockwaveFlash">');
 document.write('</embed>');
 document.write('</object>');
} else if (!(navigator.appName && navigator.appName.indexOf("Netscape")>=0 && navigator.appVersion.indexOf("2.")>=0)){
document.write('<img src=http://www.mysite.co.uk/images/logonews.gif width=269 height=135 border=0>');
document.write('</a>');
} 
//-->
</script>