Originally posted by ComputerControlled But since i have a 50mm, 135mm and an 80-200mm, not if i really need the lens.
You might want to consider the kit lens as the field of view of a lens mounted on current Pentax dSLRs is narrower than the field of view of the same lens mounted on a full frame / film bodies (factor 1.5x).
Best example with your current lenses
The 135mm mounted on the dSLR will give the same field of view as the 80-200 at 200mm on a film body.
The 50mm mounted on the dSLR will give (more or less) the same field of view as the 80-200 at 80mm on a film body.
If you can live with 80mm as the widest lens on a film body. there is no need for another lens. Else you should look at something that covers roughly 35mm. DA(-L)35/2.4 and older AF or MF lenses come to mind as well as the kit lens that you have mentioned. Although the newer kit lenses are supposed to be better, the older one is not bad (see e.g.
Pentax SMC-DA 18-55mm f/3.5-5.6 AL - Review / Test Report); unless you want a prime, I would add the kit lens for $50.