hello, sorry at the moment we can only provide support in english in this forum. for other support options in chinese please see https://support.mozilla.org/zh-CN/kb/%E8%8E%B7%E5%BE%97%E7%A4%BE%E5%8C%BA.... thank you for your understanding!

Append some details: Using FireFox 29.0, I find this case does not make sense: If there are 2 web applications in the same server, e.g: HostA:8080/app; HostA:18080/app; After logging in HostA:8080/app with pwd, I can login HostA:18080/app directly, without authentication...

you might file a bug for it at bugzilla.mozilla.org