I just noticed on an installation using core localization that in some languages  there's an issue with the containers.
The portal has a "no-title" container set and in other languages than the default one module do show a container.
Going to the Module settings the container seems empty / not set.

But in the database they have a containersrc like this: /Portals/_default/containers/myskin/h2.ascx

SELECT        Tabs.PortalID, Tabs.Tabid, Tabs.TabName, Tabs.CultureCode, Tabs.TabPath, TabModules.ModuleID, TabModules.PaneName, TabModules.ContainerSrc
FROM            Tabs INNER JOIN
                         TabModules ON Tabs.TabID = TabModules.TabID
                         where TabModules.ContainerSrc like '/portals%'

(While normally should be [G]containers/myskin/h2.ascx)
Which is why the container shows up empty in the module settings...
But DNN does render the setting in the database correctly.

(very confusing, that the dropdown is empty, but the container does show)

I'm guessing that the PB does this when translating the pages, or maybe modules localization screen?
Before I invert more time in this I woould liek to know if anybody has seen this before?
Or if you could please run the SQL on you installation to see if you also have containers starting with "/Portals" :-)