just came to my mine isnt the 1st and 2nd and 3rd and 4th still in the belly of the death god doesnt really seem for i just wanted your thoughts on if theirs a way to undo it and release all their souls or are they trapped their for eternity.
This is an interesting question, and I would say that there is some evidence that there may be a way to open the seal. Or at least, for a time, some of the story lines pointed that way.
First, consider that Minato sealed half of the Kyuubi's chakra with himself in the death god's belly. While it has been argued that this chakra has since regenerated, it was said that this was the Yin half of the chakra (and it's not clear whether it could regenerate).
Why does this matter? Because if the Kyuubi's chakra has not regenerated, then Tobi must get it in order to collect all of the Bijuu's chakra and to recreate the Juubi.
Tobi has also given a hint on how this could be done. When Nagato used the Edo resurrection technique after his fight with Naruto, Tobi says that the technique was meant for him, and that this was a betrayal.
Why should Tobi need this technique at all? There are two possible answers. For a while it seemed that Tobi may be a Zettsu clone of Madara Uchiha. This means that he could be interested in resurrecting Madara. But, he may have been preempted by Kabuto who used the Edo Tensei. Also, Nagato has mentioned that the Edo resurrection technique has limitation (he says that he was just in time to resurrect the Konoha shinobi who died during the battle). Madara has certainly died long ago...
The second possible answer is a conjecture that I have been thinking about for a while. Tobi could use the Reaper death god seal, die, and then try to get control of the Kyuubi inside the death God's belly. Then, someone (for example Nagato) with the Rinnegan could resurrect him. If this would work, it means that the Reaper death god seal could indeed be broken... from the inside ;]
