Edited Issue: How to support AjaxControlToolkit.resources.dll of Vietnamese language? [27251]

I'm using Calendar component of AjaxControlToolkit.dll, thought it support lots of language resource file(AjaxControlToolkit.resources.dll) except Vietnamese language. So I try to create an Vietnamese resource library by myself, but it doesn't work. So the issue is how can I support more language resource library?
Any suggestion?

Thanks in advance for any help!