For the love of all that is righteous PLEASE give hireling casters that should be able to have it Resist Energy. At least so they can cast it on themselves! I don't care if they can cast it on me but I get sick and tired of having fireballs and stuff bounce off my character because I drank a resist pot or have a greater resistance cloak/outfit and watch my cleric hireling keel over dead because the dang hireling can't cast a basic spell that every last character that is capable of taking the spell would be a fool not to take.
As a BONUS make it so they can cast the spell on other characters, especially characters that we are supposed to be protecting because it really sucks to get all the way thru Ritual Sacrifice and have the dork from the 12 die because neither him nor the ding-a-ling hireling can cast RESIST ENERGY.
As a SUPER BONUS give caster hirelings an 'other spells' button that the player can press to bring up a list of other (non-combat) spells the hireling knows, like other long-lasting buffs.
Thank you very much
(oh, and make sure they have extend for those... )