mapReduce error

[mercicle]

I'm trying to reproduce this tutorial using mongoskin:
http://tebros.com/2011/07/using-mongodb-mapreduce-to-join-2-collections/

And I get this error:

TypeError: undefined is not a function

/MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/base.js:242
throw message;
^
TypeError: undefined is not a function
at /MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/collection/aggregation.js:91:14
at /MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/db.js:1806:9
at Server.Base._callHandler (/MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/base.js:442:41)
at /MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/server.js:485:18
at MongoReply.parseBody (/MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/responses/mongo_reply.js:68:5)
at null. (/MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/server.js:443:20)
at EventEmitter.emit (events.js:95:17)
at null. (/MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/connection_pool.js:191:13)
at EventEmitter.emit (events.js:98:17)
at Socket. (/MyDirectory/node_modules/mongoskin/node_modules/mongodb/lib/mongodb/connection/connection.js:418:22)

[VonD]

HI,

Did you find any workaround to use mapReduce with mongoskin ? I'm considering going back to the native mongodb driver because of the lack of support for mapReduce.
Thanks for your help,

Paul