public static void setProperty(String subdomain, String name, String value) {
        MUCServiceProperties properties = propertyMaps.get(subdomain);
        if (properties == null) {
            properties = new MUCServiceProperties(subdomain);
        }
        properties.put(name, value);
        propertyMaps.put(subdomain, properties);
    }
Sets a Jive property. If the property doesn't already exists, a new
one will be created.

@param subdomain the subdomain of the service to set a property for
@param name the name of the property being set.
@param value the value of the property being set.
xmppserver/src/main/java/org/jivesoftware/openfire/muc/spi/MUCPersistenceManager.java