username with @ character error

When the username (-U) contains an @, it will assume a username on the left side and a server address on the right side of the @.

appending an extra @ followed by the same value of server (-S) fixes the issue, and it now uses the correct username and server address to sign in.

it seems to me this behavior should be fixed, since server address is a separate input argument. Or documenting this on the username argument description.