gistfile1.clj

(ns org.jtornadoweb.cljhttputils
  (:gen-class 
    :name org.jtornadoweb.CljHttpUtils
    :methods [[parseQueryString [String] java.util.HashMap]]
    :main false))

(defn #^:static 
  -parseQueryString 
  "Return all parameters in a HashMap. Same as python cgi.pase_qs. If no parameters are
  found , returns an empty Map of parameters (not null)."
  [this uri]
  (def mp (java.util.HashMap.))
  (let [q (.split (.replaceAll uri "[\\?/]" "") "[&]")]
    (if (not= (aget q 0) "")
      (doseq [i q]
        (let [pair (.split i "=")] 
          (.put mp (first pair) (second pair))))))
  mp)

Thanks Alan. As you can see I'm new to clj :P I'll try to use a clojure map instead. One point that made me use a HashMap directly was mutability. Using a Ref for a simple task like this sounds a bit overwhelming. Let see!
The previous version uses a Ref to a Clj Map, would that code slower than this last version?