Use of domain names in listen address of server config file

[idest]

I can't use a domain name to specify the listen socket address in the config file of the server. For example when using the line listen = "foo:5258" in the file server.toml, rkvm-server exits with the following message:

Error parsing config: invalid socket address syntax for key `listen` at line 1 column 10

Even though foo is a valid socket address defined in the /etc/hosts file.
In contrast the line server = "foo:5258" in the file client.toml works without problems from a client machine with an identical entry for foo in /etc/hosts. Can this be considered a bug or is this intended behavior?