inets http client url escaping

[Will Newton]

Is this expected behaviour?

9> http:request(get, {"http://localhost/index.cgi?foo=%9F", []}, [], []).
{error,no_query}

Is there a way to hex encode non 7-bit ASCII values in a path or query? I 
haven't found a canonical source on what the correct way to do this, RFC 2396 
seems to leave it open, but I would expect to be able to do that.