This reminds me of when I first discovered that you couldn't dispell "Stun". I had 1 card in hand: an Ephemeral Shroud, and even though my opponent threatened lethal next turn, I thought I had the game won.
My opponent is at 2 health, and I watch my opponent lay down the Icy, and pray that Stun isn't the ONLY effect in the game that can't be dispelled. He couldn't body block since we were both in top deck mode, and I didn't want to risk replacing my Shroud to get a Rush minion (I was Vaath) just in case the interaction worked, and I wanted to find out for future purposes.
Sad to say that upon summoning my Shroud, the only effect that was lifted was that of my BBS. Vaath remained frozen in place, with a heart as cold as the Icy that had imprisoned him. A heavy "Well Played" was handed to me right afterwards, and never again will I try to dispel a Stun effect.
I still find this interaction strange. Dispelling isn't just for spells. You can remove Shadow Creep even if made by something like Ooz (not a spell) or a Blazing Spine from a White Asp (also not a spell). But you can't dispel Flash Freeze or Frigid Corona (both spells). Why is the Stun effect above the power of dispel?