g1smd - 5:21 pm on Feb 15, 2012 (gmt 0)
The initial problem is that slashes have a particular meaning in a URL are not even a valid character in a query string name or query string value.
Overall your URL structure itself is the problem. You'd have less of a long term headache if you use folder and hyphen separated URLs with no parameters at all.
A set of internal rewrites then translate these new URL requests into the internal request pattern needed by your scripts.