The alignment-enchantments are also pretty restrictive in who can make them; only a cleric with the appropriate domain can make a holy/lawful/chaotic/unholy weapon (unless you allow Limited Wish or Miracle to sub in for the alignment-smiting spells).
Epametheus said:It's always active (as is the negative level penalty that it imposes on evil people).
I don't see why it'd be a problem. It only works on evil things, as opposed to say, working on everything that isn't immune to fire. The alignment-enchantments are also pretty restrictive in who can make them; only a cleric with the appropriate domain can make a holy/lawful/chaotic/unholy weapon (unless you allow Limited Wish or Miracle to sub in for the alignment-smiting spells).