Tried for different themes. For a non-english language in browser, using a value picker results in loading nls file for picker. Since those files do not exist, it fails.

This was an old problem (reported by Ulrich before). It's coming from the behaviour of picker.js.
1) This behavior should be corrected to prevent unnecessary errors in firebug and web logs.
2) Better than this, it would be great to provide NLS files for other languages or document a way to create our NLS files. After 3.02, dojo resources moved into JAR plugin and it's not convenient to add files into plug-in.
Thx!