user-agent required?

[Denis Haskin]

1.0RC3 seems to require a request to have a User-Agent header.  If not, 
I get a 500 error in response.

This would seem to contradict 
http://www.w3.org/Protocols/rfc2616/rfc2616-sec14.html#sec14.43 : "User 
agents SHOULD include this field with requests." (as opposed to MUST).

Thanks,

dwh