Self-signed certificates, Java, Hudson and JIRA

I'm trying to set up the Hudson JIRA plugin. Our JIRA server is secured with an self-signed SSL certificate. I've inserted the certificate my web browser has stored using the keytool command, and gotten Hudson to find it. But now it complains:

java.security.cert.CertificateException: No subject alternative names present

The common name of the certificate is "Unknown", and I do not see any subject alternative names in the certificate

$ openssl x509 -in Unknown -text -noout
Certificate:
    Data:
        Version: 1 (0x0)
        Serial Number: 1214507595 (0x4863ea4b)
        Signature Algorithm: md5WithRSAEncryption
        Issuer: C=US, ST=NJ, L=[Our town], O=[Our company], OU=[Our project], CN=Unknown
        Validity
            Not Before: Jun 26 19:13:15 2008 GMT
            Not After : May  5 19:13:15 2018 GMT
        Subject: C=US, ST=NJ, L=[Our town], O=[Our company], OU=[Our project], CN=Unknown
        Subject Public Key Info:
            Public Key Algorithm: rsaEncryption
            RSA Public Key: (1024 bit)
                [omitted]
    Signature Algorithm: md5WithRSAEncryption
        [omitted]

(Identifying info redacted and noted in brackets.)

Is there a way to attach a subject alternate name to this certificate? Or is there some other way? Or am I forced to hack the Hudson Jira plugin?