Ok, I just found this on NeoGAF. Hopefully it's true.

Another update for EU players. The first and second Hokage will be added for free to the store... next year in April.

• November 6, 2008: Character: Shizune: Mission: Aim for Higher Goals.
• December 4, 2008: Character: Asuma: Mission: Intense hide-and-seek battle.
• December 18, 2008: Character: Kurenai: Mission: Inuzuka clan's challenge.
• January 8, 2009: Character: Anko: Mission: Grand order to capture Jiraiya.
• January 22, 2009: Character: Jirobo: Mission: The three siblings' evaluation.
• February 5, 2009: Character: Kidoumaru: Mission: The Hidden Sand challenges again.
• February 19, 2009: Character: Tayuya: Mission: A new squad is formed.
• March 5, 2009: Character: Sakon: Mission: Desperate successive battles.
• April 2, 2009: Character: The First Hokage: Mission: Overflowing dangerous power.
• April 2, 2009: Character: The Second Hokage: Mission: Surpass your predecessors.