Site cannot be deployed when part of release plugin, scp method used and server uses ECDSA

When running mvn release:perform release plugin runs site-deploy. Configuration of distribution of site uses SCP protocol. So, when it comes to deploy a site SSH connection is being made. However "The authenticity of host [target_host] can't be established". What was strange I had no problems in calling "ssh target_host". There was no problem with establishing authenticity of host, neither with logging in using key. Due to this:

http://jira.codehaus.org/browse/MRELEASE-424

it was also impossible to answer the question about adding this key to ~/.ssh/known_hosts, so whole build just hang.

What I noticed my known_hosts file contained something like:
target_host ecdsa-sha2-nistp256 AAAAE2V[...]

When I've replaced this entry with:
target_host,10.0.0.2 ssh-rsa AAAAB3N[...]

everything started working. Does that mean Release plugin (or Wagon, or JSCh?) cannot use ECDSA?