I've tried out the proposed patch, and it works to the effect that the debconf setting is not overwritten. Confusingly, however, you will still have a /var/lib/samba/passdb.tdb at the end, because it is created automatically by smbd.
Perhaps the question needs to be rephrased, something along the lines of: Copy the operating system user database from /etc/passwd to the Samba password database /var/lib/samba/passdb.tdb? -- To UNSUBSCRIBE, email to [EMAIL PROTECTED] with a subject of "unsubscribe". Trouble? Contact [EMAIL PROTECTED]