MongoDB and MongoJS - can't get runCommand to work for text queries

My goal is to use MongoDB's (2.4.4) text command from Node. It works fine from the command line. Based on this previous SO issue: Equivalent to mongo shell db.collection.runCommand() in Node.js, I tried using MongoJS (0.7.17) but can't make it go. Here is the code:

mongojs = require('mongojs');
var products = mongojs('localhost:27017/mydb').collection('products');
products.runCommand('text', {search: 'a'}, function (err, docs) {
   ...
});

docs returns undefined and err is null. I can execute a normal function such as products.find() fine... and I can execute the search on the MongoDB command line. Anyone know how to make this go?

BTW, here is what docs contains in the callback:

{
    "queryDebugString": "||||||",
    "language": "english",
    "results": [],
    "stats": {
        "nscanned": 0,
        "nscannedObjects": 0,
        "n": 0,
        "nfound": 0,
        "timeMicros": 55
    },
    "ok": 1
}

BTW, if there's another approach to make this work with just the normal native driver, I'm fine with that.

Using the native driver I can run a command off of the db object as follows:

var MongoClient = require("mongodb").MongoClient;
MongoClient.connect(database, function (err, db) {
    if (!err) {
        db.command({ distinct: "Messages", key: "session" }, function (err, result) {
            //more code here
        });
    }
});

I noticed you are running the command off of the collection object, that might be the problem.