Grenadier( Player's Handbook II, p. 79)
[Fighter Bonus Feat, General]
You are skilled in using grenadelike weapons. You excel at tossing them to just the right spot to maximize the amount of damage they cause as they burst open upon the battlefi eld.
Mad Alchemist (PH2) ,
You are an expert with splash weapons and all manner of incendiary mixtures. You gain a +1 bonus on attack rolls with splash weapons and a +1 bonus on the weapon's damage (including splash damage).
A fighter can select Grenadier as one of his fighter bonus feats.