You'll find alot of information on this in this thread as well.

It can also be done successfully with a prot warrior, a resto shaman, and possibly a bear tank.

With the shaman
I would suggest you use Earthen Elixir, Earth Shield, Lichen Guard shield, Healing stream totem, Stoneskin totem and Wrath of Air. Basically the Lichen Shield will tag the mobs for you, all you have to do is stay alive while mobs are beating on you. Earth Shield and Healing Stream totem should do this alone if you're sufficiently geared. I'm in Kara/GL/ZA gear and never had to do anything else, and mana regen makes me stay at 100% mana.
Advantages:
- none really, but if you only have a shaman available you can do it :-)
Disadvantages
- costly. As you only block 5-10% of the attacks, you gear will all be damaged, giving you high repair costs. My shaman can last about 40 minutes before he needs to go repair.
- slower xp than paladin/warrior. Due to the low block rate, not all mobs will be tagged, and therefore you will miss some skellies and not get xp for those.
over the 40seconds they are spawned they will each hit you about 15-20times, so still a good chance they get tagged, but not all.
- You need to use you high level gear to do this as you'll need good healing/regen and armor to mitigate the damage. The lichen guard is an easy solution for tagging mobs, but you can also use a iron shield spike on a different shield if you want.


With the Warrior
All you need is enough avoidance to be untouchable by level 49 mobs. Someone recommended the "tankpoints" addon to check this and it helped me lots to check my avoidance.
With enough dodge/parry/block and the miss chance, you'll eventually never be hit by the mobs. It doesnt matter how much hp or armor you end up having because no skeleton will ever harm you... until your shield is broken.
Advantages
- Cheap. Only your shield gets damaged, and since armor is not important here (avoidance is, not mitigation) you can use a white shield that you find on vendors in starting zone.
Note however that with 40%+ block your shield will get damaged *very* quickly, so try and get the cheapest shields with the highest durability you can. I've used "Metal Buckler" which has 85 durability and costs 1g30 to buy, and about 9silver to repair when at 0 durability.
- Efficient. to have that much avoidance you'll probably pack about 40-45% block. which means that the shield spike on your shield will most probably tag all the skellies that hit you, giving your all all the xp you can get from these. Also, as long as you have shields to use (with spikes) you can last forever. Only your shield gets damaged, the rest of your armor does not.
- It is something quite enjoyable to have about 40-50 skeletons on you, and see a stream of block/miss/dodge/dodge/block/parry/block/miss/dodge... on your screen :-)
Disadvantages
- you need to be well geared to be able to pull this out, I've done it with a warriro geared in GL/ZA/Kara gear but if you have lower avoidance and you will get hit, eating through your hp and durability little by little. Eventually you will need a heal and repairs. With enough block however, using the figurine of the collossus at any time will refill you hp bar completely (+10-12K hp easy)
Note, a "Metal Buckler" lasted about 5-8 minutes when used on the warrior

My shaman's gear can be found here
My wife's warrior can be found here
Note that i tried to do it with my own warrior (here) and could not do it.

Hope this helps.