OpenLayers and Rails: how to set up a ProxyHost?

Dear all,

I'm using OpenLayers (and GeoExt) to embed an interactive map in a rails application. Things work pretty well with WMS requests, but now I'd need to implement a GetFeatureInfo feature. This requires the XMLHTTPRequest object, through which requests to remote servers are not allowed. Read the details here:

OpenLayers - Welcome#ProxyHost

Usually, this limitation is worked around with the set up of a cgi script in the web server that works as proxy. The question then is how can this made with Rails? Can somehow Rails run a cgi? Or somehow make a view work as a proxy?

Thank you,