Spears could be easily added to the game without having to code a whole new set of animations (this is the only thing I can think of that has held them up (along with other polearms) from inclusion in the game since launch).
The only graphic work needed would be the looks of the spears themselves. Simply using the quarterstaff attack animation for them (adjusting the speed a bit) would work just fine. I mean if we have people 'thrusting' with maces and the like, who really cares if our characters all use spears like shaolin monks do? Just get them in the game!!!
As for the thrown aspect of spears, that would fall under the same category as every other thrown weapon - either stacks of 20 (which I assumes donates a 'low-grade' weapon that can be thrown 20 times before becoming useless) or returning types. Use the spear throwing animation that Hobgoblins have already combined with the sunflask toss animation for characters - it may not look pretty, but we don't care - get spears in the game!
For the whole 'reach' part of spears - just ignore it for DDO. It overly complicates the combat system (and I hope isn't another reason spears have been left out of the game so far)
Honestly all polearms could be included this way (just use the quarterstaff attack animation and ignore reach) - but the spear, one of the most basic and ubiquitous weapons that man has ever made, needs to get its day in the sun in DDO. Please Devs, please, after more than 5 years of waiting, can't someone just green light the above 'quick fix' suggestions to fast track spears into the game?