Cookie encoding problem

Gurus,

I'm new to the rail stuff and didn't find any answer to this on the
net:

1. In RoR I set a cookie to a value like "/foo/bar" (containing
slashes and other special chars)
2. In my bowser I see that the value is actually "%2Ffoo%2Fbar" (URL
encoded)
3. This cookie will be received by an app which does not decode the
URL encoded value

Is there a way to prevent cookie encoding on the RoR/Mongrel side?

TIA

Steffo