Errore DB Mongo:operatore non valido:$cerca durante la ricerca di $testo

In mongo 2.6+ $text funziona come segue:

db.collection.insert({desc: "This is a string with text"});
db.collection.insert({desc:"This is a another string with Text"});
db.collection.insert({desc:"This is a another string with ext"});
db.collection.ensureIndex({"desc":"text"});
db.collection.find({
    $text:{
        $search:"text"
    }
}); 

Questo darà l'output come:

{ "_id" : ObjectId("553277a608b85f33165bf3e0"),
 "desc" : "This is a another string with Text" }

{ "_id" : ObjectId("5532779f08b85f33165bf3df"), 
"desc" : "This is a string with text" }

Inoltre, se stai utilizzando mongo versione 2.4, utilizza quanto segue:

 db.collection.ensureIndex({"desc":"text"});
 db.collection.runCommand( "desc", { search: "Text"})