Using Notes://. How to read the query_string parameters in Notes?

I'm using "Notes://...?open&Code=123" as a url from a browser. This works perfectly. However, I need to be able to read the query_string provided in the url. Trying this with e.g. an ?Openform, resulted in an empty string. I tried opening an agent using Notes://...myagent?Open, but this didn't work at all ! Update: I've added it to IdeaJam !