Go-libp2p examples with non tcp protocols

Hi fellow p2p hackers, trying to run the go-libp2p echo example with a protocol other than tcp. Any idea why it won’t work with a muliaddress that specifies a protocol such as /ip4/127.0.0.1/udp/%d/udt or /ip4/127.0.0.1/udp/%d/utp. Getting the following error when trying one of these:

swarm cannot use any addr in: [/ip4/127.0.0.1/udp/4002/udt]

Am I building a malformed multiaddress? I’m following the multiaddress format specified here: https://github.com/wking/ipfs-specs/tree/master/protocol/network

Trying to verify lib-p2p UDP and UTP protocols support.
Is this a known issue?
Thanks for the info!

I can’t get the echo sample to work with any non-tcp multi-address. Did anyone have better luck? Trying to test the protocol-agnostic nature of lib-p2p and use over udp.