Unauthorized connection for splitChunk results in unhelpful error message.

http://buildbot.mongodb.org/builders/Linux%2064-bit/builds/3755/steps/test_3/logs/stdio/text

m40000| Fri Oct 14 22:27:04 [conn12] assertion 10057 unauthorized db:config lock type:-1 client:10.110.9.236 ns:config.shards query:{}
m30999| Fri Oct 14 22:27:04 [conn1] warning: splitChunk failed - cmd: { splitChunk: "test.foo", keyPattern:

{ _id: 1.0 }

, min:

{ _id: MinKey }

, max:

{ _id: MaxKey }

, from: "bs-linux64.10gen.cc:30000", splitKeys: [

{ _id: 1.0 }

], shardId: "test.foo-_id_MinKey", configdb: "bs-linux64.10gen.cc:40000" } result:

{ errmsg: "exception: field not found, expected type 2", code: 13111, ok: 0.0 }

{
"cause" :

{ "errmsg" : "exception: field not found, expected type 2", "code" : 13111, "ok" : 0 }

,
"ok" : 0,
"errmsg" : "split failed"
}
assert failed