I don't think so, but one of my players does (see quote below):
"If Tom the rogue deals cold damage (Frost weapons have an at will ability that allows you to convert all damage dealt by the weapon to cold and grants the attack the cold descriptor) to a creature with cold vulnerability (Lasting Frost - Any target you hit with a power that has the cold keyword gains vulnerable cold 5 until the end of your next turn.) with any of his powers the target grants her combat advantage (Wintertouched - When attacking a creature that is vulnerable to cold, you gain combat advantage when you use a power that has the cold keyword) until the end of her next turn."
You can see where he's going with this…
"If Tom the rogue deals cold damage (Frost weapons have an at will ability that allows you to convert all damage dealt by the weapon to cold and grants the attack the cold descriptor) to a creature with cold vulnerability (Lasting Frost - Any target you hit with a power that has the cold keyword gains vulnerable cold 5 until the end of your next turn.) with any of his powers the target grants her combat advantage (Wintertouched - When attacking a creature that is vulnerable to cold, you gain combat advantage when you use a power that has the cold keyword) until the end of her next turn."
You can see where he's going with this…