I would go with Dave's way or replace directly in the database file.
That is what I am trying to do, but it doesn't work.
Dave suggested:
UPDATE post SET pagetext = REPLACE(pagetext, 'olddomain.com', 'newdomain.com') WHERE pagetext LIKE '%olddomain.com%'
So I did:
UPDATE post SET pagetext = REPLACE(pagetext, 'dutchfleet.net', 'dutchfleet.nl') WHERE pagetext LIKE '%dutchfleet.net%'
But I get:
#1064 - You have an error in your SQL syntax; check the manual that corresponds to your MySQL server version for the right syntax to use near ')' at line 1