Gem install postgres, dead meat - revisited

I’m still trying to install this sucker … (RR)

I’m behind a firewall on a WinXP machine.

I open up a DOS window, go to my RR sample app and type the following to
set up postgres:

gem install postgres

I get back the following error:
ERROR: While executing gem … (SocketError)
getaddrinfo: no address associated with hostname.

So … I create this environment variable (info from a prev post):

set http_proxy=“xxproxy:8080”

and rerun the gem command.

I now get this error:
ERROR: While executing gem … (URI::InvalidURIError)
bad URI(is not URI?): “xxproxy:8080:”

Any ideas ?