I have several ideas.

I work for a company that makes transparent proxy software. Microsoft's proxy products don't behave in the manner that other proxies do. When we have issues with our proxy breaking things, we sniff the network and watch the request come though. Some proxies are extremely sensitive to HTTP requests, and require special formatting of HTTP headers to work correctly. For instance, here's a typical HTTP request from an average program:

GET www.google.com/index.html HTTP/1.0
[download]

This code will fail on most proxies because proxies require an additional header. So the following request will work on most proxies:

GET /index.html HTTP/1.0
Host: www.google.com
[download]

Now this works on virtually every proxy. Except WinProxy. WinProxy requires an additional header, as well as browser identification, so the same request would look like this:

GET / HTTP/1.0
Host: www.google.com
User-agent: Mozilla/4.7 
Remote-Host-Wp: 10.0.3.82
[download]

Aparently the session management part of WinProxy is severely lacking.

So the point to all of this is that writing to WinProxy is extremely difficult (do a query for "WinProxy" in Mozilla's bug tracking database, and see how WinProxy breaks everything). My suggestion is to sniff the request, figure out where the proxy is dying, and use LWP::UserAgent to fake the headers WinProxy requires.

Sorry for the rant :-)

BlueLines

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