mongod-2.7.7-pre- test> db.dropDatabase();db.a.insert({a:Timestamp(-2, 3),b:"hello"})
Inserted 1 record(s) in 127ms
WriteResult({
  "nInserted": 1
})

mongod-2.7.7-pre- test> db.a.find()
Error: 17355 Error converting Timestamp 4294967294000|3 in field a to a JS Timestamp object: Error: The first argument must be in seconds; 4294967294 is too large (max 2147483647)

{ "_id" : ObjectId( "542d7d84f7ba5b99e472c84c" ), "a" : Timestamp( 4294967294, 3 ), "b" : "hello" }