Is this normal spell-casting ai behavior ?

[Wauthan]

AI seem to prefer summoning spellls over dealing damage when the battle is far away from them. Great legions of souless and skellingtons shambling about the rear ranks tends to be evidence of this.

To remedy this you need to get your spellcaster closer to the enemy by scripting in a few attack commands. It's risky but it makes the spellcaster more useful since many good spells have a fairly limited range. The spell Haste is a good way to get the whole lot of spellcasters running to the frontline with just one attack command. Flight is a little bit too risky without serious protective spells and equipment.