Try this. You are missing an open parenthesis that's why you are having the parse_simpleexpr: unmatch ')' error.
24099,Black_Flaming_Fairy_Wings,Black Flaming Fairy Wings,5,20,,100,,0,,1,0xFFFFFFFF,31,2,1,,0,0,32003,{ if ((Class==Job_Assassin_Cross) || (Class==Job_Champion) || (Class==Job_Clown) || (Class==Job_Gypsy) || (Class==Job_Star_Gladiator) || (Class==Job_Stalker)) bonus bAgi,285; bonus bDex,285; if ((Class==Job_Lord_Knight) || (Class==Job_Paladin) || (Class==Whitesmith) || (Class==Creator)) bonus bDex,285; bonus bStr,285; if ((Class==Job_High_Wizard) || (Class==Job_Professor) || (Class==Job_Super_Novice) || (Class==Job_High_Priest)) bonus bAgi,285; bonus bInt,285; if ((Class==Job_Gunslinger) || (Class==Job_Sniper)) bonus bDex,350; if (Class==Job_Ninja) bonus bStr,230; bonus bAgi,230; bonus bDex,230; },{},{}
Edit: Ainna, you type fast.