Hi,

Most of modules (at least the critical one) has been ported to D6 for the status I know ATM. There a still 2 modules to update to have an usable (but not production ready) version, it's the product module and the CA module.

The product module is actually broken because it have dependencies with imagefield and imagecache, and imagefield don't have a 6.x version ATM. There is gapdev that update the product module to remove deprecated stuff and make it compatible with the CVS version of imagefield that is for Drupal 6, but it's far from beeing ready for a production website.

The CA module will replace workflow, if I understood well, the system works OK, but there is no UI to manage your rules.

So it is not ready for a production site, not so far, but not yet. Don't know your deadline but if you have to finish it before the summer, I suggest you to keep 5.x and manage multilanguage with i18n. In addition, i18n is really buggy on d6 ATM and it works better on D5.