The patch looks fine to me (it had better be, since it is already pushed :P), however I wonder if it wouldn't be prudent to look to moving define-record-type into guile proper, and making (use-modules (srfi srfi-9)) effectively a no-op.
-- Ian Price -- shift-reset.com "Programming is like pinball. The reward for doing it well is the opportunity to do it again" - from "The Wizardy Compiled"