The [Same Origin Policy Documentation](https://developer.mozilla.org/en/Same_origin_policy_for_JavaScript) says this:

> 
> There is one exception to the same
>  origin rule. A script can set the
>  value of document.domain to a suffix
>  of the current domain. If it does so,
>  the shorter domain is used for
>  subsequent origin checks. For example,
>  assume a script in the document at
>  <http://store.company.com/dir/other.html>
>  executes the following statement:
> 
> 
> document.domain = "company.com"; 
> 
> 
> After
>  that statement executes, the page
>  would pass the origin check with
>  <http://company.com/dir/page.html>.
>  However, by the same reasoning,
>  company.com could not set
>  document.domain to othercompany.com.
> 
> 
> 

Do all popular browsers support this? If not, which ones don't?