BUG: Output of date in wrong time format for cookie expiration (fixed)

Altered test output to match correct name of gem needing to be installed for memcache

lib/rack/session/abstract/id.rb

@@ -1,6 +1,8 @@
 # AUTHOR: blink <blinketje@gmail.com>; blink#ruby-lang@irc.freenode.net
+# bugrep: Andreas Zehnder
 
 require 'rack/utils'
+require 'time'
 
 module Rack
   module Session
@@ -101,11 +103,13 @@ def commit_session(env, response)
             return false
           end
 
-          expiry = options[:expire_after] && time+options[:expire_after]
           cookie = Utils.escape(@key)+'='+Utils.escape(sid)
           cookie<< "; domain=#{options[:domain]}" if options[:domain]
           cookie<< "; path=#{options[:path]}" if options[:path]
-          cookie<< "; expires=#{expiry}" if expiry
+          if options[:expire_after]
+            expiry = time + options[:expire_after]
+            cookie<< "; expires=#{expiry.httpdate}"
+          end
 
           case a = (h = response[1])['Set-Cookie']
           when Array then  a << cookie

lib/rack/session/memcache.rb

@@ -9,11 +9,12 @@ module Session
     # Session data is stored in memcached. The corresponding session key is
     # maintained in the cookie.
     # You may treat Session::Memcache as you would Session::Pool with the
-    # following differences.
+    # following caveats.
     #
     # * Setting :expire_after to 0 would note to the Memcache server to hang
     #   onto the session data until it would drop it according to it's own
-    #   specifications.
+    #   specifications. However, the cookie sent to the client would expire
+    #   immediately.
     #
     # Note that memcache does drop data before it may be listed to expire. For
     # a full description of behaviour, please see memcache's documentation.

test/spec_rack_session_memcache.rb

@@ -114,5 +114,5 @@
     end
   end
 rescue LoadError
-  $stderr.puts "Skipping Rack::Session::Memcache tests (Memcache is required). `gem install memcache` and try again."
+  $stderr.puts "Skipping Rack::Session::Memcache tests (Memcache is required). `gem install memcache-client` and try again."
 end