While a lot of loose ends will seemingly be tied up with ROTS, there's one that still has me puzzled.

In The Phantom Menace, Maul says he was able to trace Qui-Gon Jinn and company to Tatooine (presumably thanks to receiving a response to Sio Bibble's transmission -- the one which Obi-Wan said was a trick and not to respond to). What I am still not clear on is this: who exactly responded to the transmission?

I personally always assumed it was Padme, since she's the one who replays the holographic message later aboard the ship while en route to Coruscant (almost as though she's questioning her earlier actions and/or feeling guilty). Anyone have any thoughts on this?

here's the actual dialogue:

Qui-Gon: It sounds like bait to establish a connection trace (said in response to Obi-Wan telling him about Sio Bibble's transmission),

and

Darth Maul: Tatooine is sparsely populated. If the trace was correct I shall find them quickly, Master (said to Sidious on the balcony at Coruscant).

This dialogue would seem to indicate that Maul indeed was able to track our heros to Tatooine due to someone responding to the transmission, just as Qui-Gon had predicted.

This being the case, I can only see 2 possible explanations as to who sent the transmission. The first, and most probable, is that Padme herself replied out of worry/fear for her people (see my earlier post), and that this simply occurred off-screen. The other possibility is that there was a traitor among our heros.

I've heard people (jokingly) suggest anyone from Panaka to R2 could be the spy in question, but this seems way too sheep to really be the case. Like I said, I'm sure it's just Padme, but the lack of concrete evidence has always made me question this point.

occam's razor

"It sounds like bait to establish a connection trace."

People make this scene way more complicated than it is. No one sent a covert reply back to Naboo.

Sounds to me like merely recieving the message was enough to establish a trace.

Modern day phones can be traced by answering a call. You don't have to hang up and call the FBI back for them to discover your location. However, once they have your number you can be traced everytime you make another call.

Maybe Obiwan didnt want a reply sent back because it would verify that their ship was not moving.

Especially if you have a cell phone. My advice to you is if you dont want anybody to know your shit, don't say it on a cell phone/sat phone. Landline is about as secure as it gets without a tap or trace being put on it. Its not that much of a stretch to figure out that our heroes were on tatooine. The enemy knows that they have to be going to coruscant. They probably knew that the hyperdrive was leaking.(Sensor readings) They knew they would have to be somewhere where there is minimal TF presence. All they had to do was monitor transmissions from those general areas to and from Naboo. Then theres that force thing that DS does....