HTTP Proxy messes up metadata

[UnConeD]

(first of all, sorry if this question has been asked before, but I did a forum search and located nothing related to my problem)

I have a problem listening to certain streams. The reason is my ISP, which doesn't allow outgoing connections on the HTTP port (80). Instead, I have to use an HTTP proxy-server.

Now, it seems whenever I listen to a shoutcast station through the proxy, Winamp thinks it's a regular MP3 stream instead of a Shoutcast stream, and the metadata about the stream is 'played', resulting in a short skip every second or so. This of course makes it impossible to enjoy the music.
This is only a problem for stations that run on the standard port (I can connect directly to others).

I was wondering if anyone had the same problem and had found a way to get around it: either by removing the metadata or making Winamp ignore/recognize it.