They don't need to support those. As mentioned by Roman you could build the entire LN in one contract. You can even implement the LN Relative OP_CHECKLOCKTIMEVERIFY requirement in a much better way.

In fact you can add more functionality than is possible with the Bitcoin LN, you could allow people to add more Ether to their side of the channel with offchain transactions.

Tx malleability also doesn't need to be solved (a very difficult probelm in Bitcoin) because it doesn't pertain. A LN contract wouldn't have to chain offchain transactions in any way, just passing signed offchain 'notes' of a sort that contain information relating to amounts, blocknumber for available release, etc...

It is also somewhat trivial to add the hub and spokes part where a random value R is hashed to create H and allow payments to hop through multiple parties (but in Ethereum you could do it without the problem of locking up funds that they need an extra OP CODE to solve).

Disclosure: I'm actually working on this in my spare time.