I got it. I have to :or it with :is-null, like this:
(sql (:select '* :from 'table :where (:or (:like 'field "%something%") (:is-null 'field))))
Good to see you figured it out!
(As an aside, please try to actually reply to your thread, rather than starting a new one for each mail. I'm not sure what you did wrong, but both gmail and the mailing list archive show this conversation as four different threads.)
postmodern-devel@common-lisp.net