How do I translate quicktab headings?
Ensure you have downloaded (if needed) and enabled the 'Locale', 'Internationalization', 'String translation' modules
Go to Configurations > Translate Interface > Strings (Tab) (admin/config/regional/translate/i18n_string)
Check the 'Quicktabs' checkbox under the 'Select text groups' heading, and click 'Refresh strings'
Go to the page where it the quick tabs is and refresh it a few times (normally, you WOULDN'T need to do this, but for me, if I didn't and it's not cached, it doesn't work)
Go back to Configuration > Translate Interface > Translate (Tab) (admin/config/regional/translate/translate) , and search, using the 'String contains' input box, for one of the tab titles. I.e. if your tab titles are 'Apples', 'Oranges' and 'Pears', search for 'Apples'.
You should be able to see an entry. Click 'edit' and translate away!