Edo Tensei requires a certaina mount of DNA or the soul must not be sealed in order to revive someone.
Nagato didn't revive him because too much time has passed from his death to that of him attacking Konoha.
Jiraiya is dead, wont be back with Edo Tensei, well, IF Kabuto finds some DNA of Jiraiya but it's currently on the ocean floor, but what I don't understand is Kabuto is like a scientist you know, why not take a little tiny bit of DNA from Jiraiya(possibly everywhere, that perveerted guy lol) and replicate it with somem forbidden jutsu and bring him back.
Or use that Giant snake that attacked the Turtle Island and have it sniff out Jiraiya.
