How to decrypt a URL

I encrypted a url that i would like to pass to another page, but can't seem to get it to decrypt it. This is the first time i am using this technic, so i might not be doing it right. Just been reading alot of the examples on the web and can't get it to work for me.

== Encrypted ==

<h3>URLEncodedFormat Example</h3>

<cfscript>

  theKey=generateSecretKey("AES");

  encrypted=encrypt(#qEdit.PersonID#, theKey, "AES", "HEX");

</cfscript>

<cfoutput>

  <a href="##" onclick="MM_openBrWindow('test2.cfm?Picture=#encrypted#','','resizabl e=yes,width=500,height=500')">Test Encode</a>

</cfoutput>

The encryption works fine in the url, but now i'm not sure how to decrypt it on my other page.