The 35 year old last played a competitive game in April was training with Bolton Wanderers last week was a free agent and has signed a deal with the Millers until January.
Odemwingie is looking forward to working with Jackett, speaking to the clubs official website themillers.co.uk he said "He is a manager that believes in you and that gives me a lot of positivity. He obviously believes in me and thinks I can do a job for him, so I am looking forward to a new start and doing my best for the team."
"I am looking forward to this, I love pressure as a player, I love situations like this, and a lot of times I have delivered, I hope it will be the same in this club. I want to play out of my skin because there is a level that I want to get back to and the only way to get back to that is to do my best and work really hard."
"It has been a while but I have tried to stay fit and keep on top of things. I have had a few training sessions in the last few days and I feel ready to go, I don't think it will take me long to get back to my best." he added.