Took a few minutes to convince myself that there is no un-encode for server.urlencode in stock ASP/Vbscript.
I ended up using the decode function here:
http://www.vyomworld.com/lib/script_description.asp?ScriptID=127
to convert the previously encoded string into something an unencoded string that I could use again. It seems to be a glaring ommission in ASP, but at least there are supposed to be some functions in ASP.net to handle this issue in the future.