The Whites have been missing a right handside midfielder since Aaron Lennon left for Tottenham last summer.
"I'll practice with them Monday to Friday and then see Saturday's game against Cardiff," he told Swedish club Orebro's official website.
"I am planning to stay with Orebro until something more interesting comes along and this is definitely more interesting," the 25-year-old added.
Anttonen has just one year left to run on his current contract with Orebro.