Actually, thats not TOO bad an idea, granted there are extreamly tight limits. Make the spell that can be "imbued" into the item 3rd lvl or lower (and have the caster lvl cut off at 8 or so)
Also, make it so that it is EXTREAMLY expensive to do so, maybe even require a series of special permissions by the gods to do so, and even then you can only do it less then 5 times, and then never again. And limit it to the 5 times per cd key, instead of just char. That should put a resonable limit on the amount of items like that in world.
I can only see this being workabe for mages and sorcs, because i dont think you'll have clerics who want to make a mace that cures light wounds on each strike
