The new deal will keep Thomas at the club until the summer of 2012 and the club have an option to extend it by a further year.
“I’m really happy, I had a good season and I’ve been rewarded for that,” the 27-year-old told the club’s website.
“I feel I put a lot of good performances in last season.”
“When I injured my back and missed a season at Portsmouth, it was a reality check on how quickly it can all go,” he added.
“So, I worked extra hard last season and it’s paid off. The club know my injury is not an issue now.
“I’ve come back in early for pre-season training to do my strengthening work and I feel good.
“My job is to set up goals and score goals – If I’m not doing that I’m not doing my job.
“I think I was consistently a threat last season and I’m glad the club have recognised that and rewarded me with a new deal.”