I developed an OSX service using Automator, and installed the workflow for all users in /Library/Services.
The workflow packet contains a folder Contents, and within it the file Info.plist and a folder Resources.
Resources contains for every localization a folder with the language code as name, and lproj as extension.
Each of these folders contains a strings file ServiceMenu.strings.
Info.plist contains among others the default menu item title (in my example : "New entry in contacts").
Every ServiceMenu.strings file contains the localization of this default title. In the example for Spanish and Simplified Chinese.
The problem is that the default title, as well as the localizations in German & Spanish do work, but the localization in Simplified Chinese does not:
When I set in my Mac in Settings/Preferred Languages to English, German, or Spanish as the 1st language and re-boot, the service menu entry is correctly displayed in this language.
But when I set Simplified Chinese as the 1st preferred language and re-boot, the menu entry is not displayed in Simplified Chinese, but in the language set as the 1st preferred language before the re-boot.
Obviously, the problem is not that the localization is not found - in this case, the default menu entry in Info.plist should be shown, but not the entry in the language set before re-boot.
This seems to me to be a OS-X bug. It behaves the same in Mavericks & Yosemite.
Any idea what I could do?
I submitted a Technical Support Incident (TSI) to Apple and received the answer that this is an OS X bug (I will file a bug report).
A workaround is to name the respective folder not "zh-Hans.lproj" as the standard requests, but "zh_CN.lproj" instead.
With this name the menu entry appears correctly in Simplified Chinese.