How can I get Achievement title? (iPhone Game Center)

I am trying to show achievement title when the player earns that. I am doing it exactly like Apple's GKTapper sample:

NSLocalizedString(ach.identifier, NULL)

(ach is of type GKAchievement)

In GKTapper this line returns the title (e.g. "One tap!"). But in my own application, this returns the Achievement ID (e.g. com.companyname.gamename.achievementid)

My achievement reference name is "Jackpot!" and I only added one language (English). The title of th开发者_开发技巧e achievement in English is also "Jackpot!"

Thanks

GKTapper uses a Localizable.strings file. Look for it in the resources folder.

NSLocalizedString(@"com.appletest.one_tap", NULL) is paired with @"Just One Tap";

(in the version of GKTapper I'm looking at)