Paladin's Hand of Reckoning

Shouldn't Paladin's Hand of Reckoning reflect Warrior's Spell Reflect and eat Shaman's Grounding Totem?

Because it is considered as a spell.

On my two previous WotLK SCRIPTED and populated servers it was working like I described above. ^^

I don't know if it's the case but it was determined that in retail some spells such as Mind Soothe did not trigger Spell Reflect or Grounding Totem.

It is right that pve (and some also are no GCD) spells don't trigger such important pvp spell, otherwise it would be abused lime previously target macro for pets to kill shaman totems

Well, if memory serves Hand of Reckoning is considered as a holy spell, therefore it is a spell.

I don't think that it should kill shaman totems but I am sure that it should reflect warrior's spell reflect and eat shaman grounding totem.

How is hunter's pet growl killing the grounding then? ;)

I don't know if it's the case but it was determined that in retail some spells such as Mind Soothe did not trigger Spell Reflect or Grounding Totem.

Hand of reckoning have zero iteractions with players, it's pve only spell with bo mechanics that come into action with players - therefore there is nothing in it to trigger spell reflection

Well, on my two previous WotLK SCRIPTED and populated servers it was working like I described above tho...

We can't know for sure that this two servers were scripted RIGHT. And considering that warmane is one of most popular servers of wotlk with lots of players back from retail, there in no other threads about HoR spell - so i highly doubt that it was coded right on your servers. Once again, taunts have no effect on players > shouldn't trigger spell reflect (because it have NO working element in it that affects player).
You can try to report it as bug to see answer from dev-team. Or just go to paladin class sub-forum.