Please see the attached screenshot. Its tooltip message is displayed in English only.
Steps to reproduce:
1. Move to My Workspace -> Preferences -> Language, and choose a language except for English.
2. Move to a worksite -> Announcements -> Add, and choose the availability to specify dates. (These messages in the steps should be in the specified language.)
3. Then the tooltip on the calendar icon is displayed as English 'Popup date selector'.
That's one small tooltip for Sakai, may need several fixes for components. The attached patches are for Announcements, Reference, and Velocity components.