event target bug or jquery.validation bug in IE?

I'm using jquery.validation.js plugin. It works fine in firefox.

However, in IE, I have problem if there is errorred fields (which shows
an error sentence). If it happens, the plugin keep onfocusin the first
errored field (i use the event object to find out the problem). It
should be logically wrong.

But it creates big problem when I then trigger e.g. an autocomplete, or
rating section. it seems that IE does not know which field it is
focusing and make the problem.