You can see a service configuration by looking the file /var/svc/manifest/system/<service-name>.xml, and in particular the command it launches, if any.
For example, system-log service shows this:
Code:
<exec_method
type='method'
name='start'
exec='/lib/svc/method/system-log'
timeout_seconds='600' />
That means the start script is /lib/svc/method/system-log , which you can modify to add options or whatever, at your own risks ...