Wells, the only way to get TRUE full divine casting is to have all domains and access to spells of any alignment descriptor. Obviously not happening, but you CAN get some Ur-Priest in there, if you want access to evil spells (or good spells, if you're evil).
Try the ol' Bard/Ur-Priest/Lyric Thaumaturge/Mystic Theurge for 9th level arcane and divine spells. A bit of MAD, but at least it's Wis and Cha, which synergize fairly well. You might even be able to become a diplomancer, if you try hard at it. But... I digress. Lyric Thaumaturge is either Complete Arcane or Mage, and Ur-Priest is complete divine. Mystic Theurge and bard obviously are core.
Also, if you're a gnome, definitely look in Races of Stone at the Divine Prankster class. It doesn't have full bardic abilities per se, but the initiate of Milil (if I understand it) stacks bard and cleric levels for bardic music in some way, and the Divine Prankster stacks for inspire courage and gets a slew of "comedic performance" which climaxes with the Killing Joke, which is really freakin' awesome. It takes 3 rounds, they make a will save to notice what's going on, and then they make a will save or die. Pretty sweet. Also it's a 10/10 class, and it has some sweet moves related to combat as well making it a rather good battlefield controller with some of its moves making the enemies attack you exclusively. A build might look like Bard 1/Cleric 9/Divine Prankster 10.