http-client port encoding failed

[mbcladwell]

Hi,

I am using http-client to submit requests that contain extended Latin  
characters e.g. "Marjanović+Ž".  I believe I have locales set up  
properly as I don't receive the "can't set locales" error.  Also I can  
regex with the extended Latin characters.

scheme@(guile-user)> (locale-encoding)
$11 = "UTF-8"

 When I submit a url containing the above Serbian name, I get the error:

Throw to key `encoding-error' with args `("put-char" "conversion to  
port encoding failed" 84 #<input-output: string 7febcf44c2a0> #\ć)'.

If I paste the URL into my browser I receive the correct response.

Prior to the request I use (set-port-encoding! (current-output-port)  
"UTF-8") without effect.
What should I do?
Thanks
Mortimer