[Mediawiki-l] interwiki table changes not seen

I changed a iw_url value in my maintenance/interwiki.sql as per http://meta.wikimedia.org/wiki/Help:Guide_for_system_administrators_for_sett... and ran the SQL to update the table for our intranet MediaWiki, and verified the change with

select * from interwiki;

but my site is not picking up the changes. I edited an article that has an interwiki link in it for the iw_prefix that I changed but when I preview/save that article, the link still refers to the old (iw_url) value.

If I add a new entry to the table, interwiki links using the new iw_prefix work and resolve to the iw_url of the new record. So I'm confident the table is being updated correctly.

Is there some interwiki caching going on that masks changes to existing rows in the table?

I'm using:

* MediaWiki: 1.5.6 * PHP: 4.4.2 (apache) * MySQL: 4.1.7-standard-log

thanks