If you're using a web browser and can get through a proxy server (say, to post to Perlmonks), then you can probably configure PPM to use the proxy server.

PPM uses LWP, and LWP can be made to use a proxy server by setting the environment variable HTTP_PROXY to the URL of the proxy server. (See LWP::UserAgent for the full details.)

I've done this. It works fine.

You may be screwed if (a) your browser is configured via the registry to download proxy settings on demand and (b) your organization has helpfully arranged for you to not have visibility into the registry and (c) you can't bribe MIS into telling you the name of the proxy server.