partial urlEncoding when using if and $request_uri

[mte03]

Update: I have turned on rewrite log. The rewrite log shows uglyID correctly
matched and sent to proxy unencoded. However in TCP dump, I can see that it
was re-encoded again. Also on the target server, I can see the incoming
request having uglyID re-encoded again.

Posted at Nginx Forum: http://forum.nginx.org/read.php?2,244573,244575#msg-244575