TypeError: Cannot read property '_at' of undefined

Hi!
I have a problem with the authentication example.

/usr/bin/node server.js
Master pid 4693
info: socket.io started
4696 listening. Go to: http://localhost:3000/
connect.multipart() will be removed in connect 3.0
visit https://github.com/senchalabs/connect/wiki/Connect-3.0 for alternatives
connect.limit() will be removed in connect 3.0
TypeError: Cannot read property '_at' of undefined
    at Model.mixin.proto._createRef (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/refs/index.js:159:20)
    at Model.mixin.proto.ref (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/refs/index.js:125:19)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/lib/auth/index.js:12:11
    at Object.fail (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/descriptor/descriptor.Model.js:291:21)
    at Object._res.fail (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/pubSub/pubSub.Store.js:81:40)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/accessControl/accessControl.Store.js:199:34
    at Object.<anonymous> (/home/lev/Projects/DerbyJS/derby-auth-master/store.js:27:9)
    at guard (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/accessControl/accessControl.Store.js:198:14)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/middleware.js:7:26)
    at Object.run [as guardQuery] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/middleware.js:10:12)
    at context.guardQuery (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/accessControl/accessControl.Store.js:48:19)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/pubSub/pubSub.Store.js:89:11
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/middleware.js:7:26)
    at Object.run [as subscribe] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/middleware.js:10:12)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/descriptor/descriptor.Model.js:257:26
    at Object.Promise.on (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/util/Promise.js:29:7)
    at Model.module.exports.server._addSub (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/descriptor/descriptor.Model.js:241:29)
    at subscribe (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/descriptor/descriptor.Model.js:290:9)
    at Model.module.exports.proto.subscribe (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/descriptor/descriptor.Model.js:106:7)
    at Object.create.subscribe.value (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/descriptor/query/query.Model.js:349:13)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/lib/auth/index.js:11:53
    at onRoute (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/lib/derby.server.js:69:7)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/node_modules/tracks/lib/index.js:84:16
    at callbacks (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/node_modules/tracks/vendor/express/router/index.js:172:37)
    at param (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/node_modules/tracks/vendor/express/router/index.js:146:11)
    at pass (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/node_modules/tracks/vendor/express/router/index.js:153:5)
    at Router._dispatch (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/node_modules/tracks/vendor/express/router/index.js:181:5)
    at Object.middleware [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/derby/node_modules/tracks/lib/index.js:48:21)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/lib/application.js:121:9
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:129:23)
    at pass (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/lib/router/index.js:110:24)
    at Router._dispatch (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/lib/router/index.js:173:5)
    at Object.router (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/lib/router/index.js:33:10)
    at Context.next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Context.actions.pass (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/passport/lib/passport/context/http/actions.js:77:8)
    at SessionStrategy.authenticate (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/passport/lib/passport/strategies/session.js:67:10)
    at attempt (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/passport/lib/passport/middleware/authenticate.js:243:16)
    at Passport.authenticate (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/passport/lib/passport/middleware/authenticate.js:244:7)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Passport.initialize (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/passport/lib/passport/middleware/initialize.js:69:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.handle (/home/lev/Projects/DerbyJS/derby-auth-master/index.js:72:16)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.handle (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/connect-flash/lib/flash.js:21:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.expressInit [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/lib/middleware.js:30:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.query [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/middleware/query.js:44:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Function.app.handle (/home/lev/Projects/DerbyJS/derby-auth-master/node_modules/express/node_modules/connect/lib/proto.js:201:3)
    at Object.fn [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/lib/application.js:118:11)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.modelMiddleware [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/lib/session/session.Store.js:119:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.session [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/racer/node_modules/connect/lib/middleware/session.js:307:7)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.cookieParser [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/cookieParser.js:60:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.methodOverride [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/methodOverride.js:48:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at multipart (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/multipart.js:90:37)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/bodyParser.js:57:9
    at urlencoded (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/urlencoded.js:49:37)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/bodyParser.js:55:7
    at json (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/json.js:51:37)
    at Object.bodyParser [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/bodyParser.js:53:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at Object.compress [as handle] (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/middleware/compress.js:182:5)
    at next (/home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/express/node_modules/connect/lib/proto.js:193:15)
    at /home/lev/Projects/DerbyJS/derby-auth-master/example/node_modules/gzippo/lib/staticGzip.js:217:24
    at Object.oncomplete (fs.js:107:15)