Issue title: express.compress() with sesion store (mongo, redis)
 Issue body: my app.configure section in environment.js file looks like:
 app.use(flash());
        app.use(express.compress());
        app.use(express.static(app.root + '/public', { maxAge: 86400000 }));
        app.set('jsDirectory', '/javascripts/');
        app.set('cssDirectory', '/stylesheets/');
        app.set('cssEngine', 'stylus');
        app.use(express.bodyParser());
        app.use(express.cookieParser('secret'));
        app.use(express.session({secret: 'secret', store: new redis({maxAge: 24 \* 60 \* 60 \* 1000 })}));
        app.use(express.methodOverride());
        app.use(app.router);

When I log out and try to login I have:

/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/index.js:525
            throw err;
                  ^
Error: write after end
    at writeAfterEnd (_stream_writable.js:125:12)
    at Gzip.Writable.write (_stream_writable.js:170:5)
    at ServerResponse.res.write (/Users/mamay/projects/node.js/kegs-node/node_modules/express/node_modules/connect/lib/middleware/compress.js:81:18)
    at ServerResponse.res.end (/Users/mamay/projects/node.js/kegs-node/node_modules/express/node_modules/connect/lib/middleware/compress.js:86:23)
    at /Users/mamay/projects/node.js/kegs-node/node_modules/express/node_modules/connect/lib/middleware/session.js:282:13
    at /Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/lib/connect-redis.js:130:18
    at try_callback (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/index.js:522:9)
    at RedisClient.return_reply (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/index.js:592:13)
    at RedisReplyParser.<anonymous> (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/index.js:265:14)
    at RedisReplyParser.EventEmitter.emit (events.js:95:17)
    at RedisReplyParser.send_reply (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/lib/parser/javascript.js:281:18)
    at RedisReplyParser.execute (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/lib/parser/javascript.js:135:22)
    at RedisClient.on_data (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/index.js:478:27)
    at Socket.<anonymous> (/Users/mamay/projects/node.js/kegs-node/node_modules/connect-redis/node_modules/redis/index.js:79:14)
    at Socket.EventEmitter.emit (events.js:95:17)
    at Socket.<anonymous> (_stream_readable.js:699:14)
    at Socket.EventEmitter.emit (events.js:92:17)
    at emitReadable_ (_stream_readable.js:382:10)
    at emitReadable (_stream_readable.js:377:5)
    at readableAddChunk (_stream_readable.js:142:7)
    at Socket.Readable.push (_stream_readable.js:112:10)
    at TCP.onread (net.js:511:21)

Exactly same behaviour when I use mongo instead of redis.
Though this issue might relate to express.

 Comments: 
 Comment 0: Not a compoundjs issue

 Comment 1: I'm having a similar issue.

```
Error: write after end
at writeAfterEnd (_stream_writable.js:133:12)
at Gzip.Writable.write (_stream_writable.js:181:5)
at ServerResponse.res.write (/var/www/pingplot/node_modules/express/node_modules/connect/node_modules/compression/index.js:111:18)
at ServerResponse.res.end (/var/www/pingplot/node_modules/express/node_modules/connect/node_modules/compression/index.js:118:14)
at /var/www/pingplot/node_modules/express/node_modules/connect/node_modules/express-session/index.js:307:13
at /var/www/pingplot/node_modules/connect-redis/lib/connect-redis.js:128:18
at try_callback (/var/www/pingplot/node_modules/connect-redis/node_modules/redis/index.js:520:9)
at RedisClient.return_reply (/var/www/pingplot/node_modules/connect-redis/node_modules/redis/index.js:590:13)
at ReplyParser.<anonymous> (/var/www/pingplot/node_modules/connect-redis/node_modules/redis/index.js:263:14)
at ReplyParser.EventEmitter.emit (events.js:95:17)
```

{'source': 'GithubIssues', 'repo_name_with_owner': '1602/compound', 'issue_id': 12970496, 'repo_stars': 1599.0}