Prestige class: Divine Archer

An archer on Diamond Island faces some severe disadvantages.  Many types
of undead have damage reduction, and it's not cost-effective to enchant
arrows as magic weapons.  Elves have a ready solution to this problem:
they become Arcane Archers, able to enchant their arrows as they launch
them.  Human paladins can't do this.  Instead, after some years of
experimentation, they have evolved a Divine Archer class.  This class
allows a paladin (or other divine magic user) to deal damage to even
powerful undead.

Rather than increase the enchantment strength of the arrow as they gain
power, Divine Archers instead have learned to add holy damage to arrows
they launch.  These arrows are far more effective against undead: even
those that ignore the arrow itself cannot ignore the holy damage it
carries.  However, the arrows are less effective against non-evil foes. 

Requirements:
Alignment: Good
Base Attack Bonus: +6
Feats: Point Blank Shot, Rapid Shot, Precise Shot
Spellcasting: Ability to cast Cure Light Wounds.

The Divine Archer:
Level   BAB     Fort    Ref     Will    Special
1st     +1      +2      +2      +0      Enchant arrow +1
2nd     +2      +3      +3      +0      Smite arrow
3rd     +3      +3      +3      +1      Enchant arrow +1/+1d6 holy
4th     +4      +4      +4      +1      Blessed arrow
5th     +5      +4      +4      +1      Enchant arrow +1/+2d6 holy
6th     +6      +5      +5      +2      Dispel arrow
7th     +7      +5      +5      +2      Enchant arrow +1/+3d6 holy  
8th     +8      +6      +6      +2      Hail of arrows
9th     +9      +6      +6      +3      Enchant arrow +1/+4d6 holy
10th    +10     +7      +7      +3      Arrow of life

Enchant arrow: as Arcane Archer, but with the bonus listed.

Smite arrow: a Divine Archer can make a smite evil attack with an arrow.
Add Divine Archer levels to Paladin levels to determine damage.  Divine
Archers that are not paladins gain the ability to smite evil once per day
(when using an arrow).

Blessed arrow: Once per day, a Divine Archer can launch an arrow that
ignores the damage reduction of any evil creature it strikes (as the Bless
Weapon spell).

Dispel arrow: Once per day, a Divine Archer can launch an arrow that
dispels any evil magic on the target it strikes.  The Divine Archer
rolls 1d20+BAB for the dispel check.

Hail of arrows: as Arcane Archer.

Arrow of life: as Arcane Archer, but the arrow forces any undead it
damages to make a Will save (DC 20) or be destroyed.