Everything grows old with time. Even certificates and the algorithms used to sign them. Luckily the standards evolve too, in order to keep the network services secure. Keys that was considered secure 10 years ago are considered toys nowadays.
This certificate has a small key and is signed with an MD5 checksum. Luckily, this kinds of certificates are not issued by any commercial CA any longer, but that doesn’t stop the TLS-O-MATIC no-guarantee CA from signing one. Your client should not connect to this server, if HTTPS is required.