Why is LeadSourceId URL parameter CaSe SenSitIve?

Can anyone tell me why the “LeadSourceId” URL parameter only works when it is typed exaclty: “LeadSourceId”?

For example, this works by assigning an appropriate Lead Source to a new contact:


But this does not work (Lead Source field is blank):

        www.grabthisfreebie.com/opt-in-page?leadsourceid=111  (all lower case)

(These are examples only)

What the heck???

Anything after a question mark in a url is not the actual url. Code that reads the parameters are usually, in them selves, case sensitive languages. It is possible to manage that behavior on the code level but it is usually preferred to use case to ensure valid information is getting sent (kind of like requiring the use of caps in passwords)