Ah, I have an answer: he's still ****ed because Babs didn't play him in Detroit. From Wiki:
Commodore has been very open over his disapproval of former Toronto Maple Leafs and Detroit Red Wings head coach Mike Babcock. Commodore has stated he was "screwed over" by Babcock while with the Cincinnati Mighty Ducks of the AHL, claiming Babcock refused to play him in favour of new addition Kurt Sauer. The relationship worsened nine years later, after Commodore signed with the Red Wings, who Babcock was coaching. Commodore states this signing is what ended his career in the NHL. Commodore claimed that Babcock misled him by telling him he was wanted as a physical presence; Commodore would remain a healthy scratch for a month and a half to start the season before playing in two games, and was then scratched again until December, only reentering the line up when, according to Commodore, Red Wings general manager Ken Holland ordered Babcock to play him. Commodore would go on to say he was traded out of Detroit "because Holland felt bad [for me]", referring to his lack of playing time.
Commodore (along with Hall of Fame defenseman Chris Chelios) also held against Babcock the fact that he healthy scratched Mike Modano when he had 1499 games played. Modano retired following that season and never reached the 1500 games played milestone. 
Following his retirement, Commodore has lashed out at Babcock multiple times, particularly on Twitter where he constantly refers to the coach as a "piece of ****". Commodore has also said he hopes Babcock "gets hit by a truck."