Replacing 404 pages with 410's automatically

Hi there,

I was wondering if anyone would be able to assist me with the following issue.

A few months ago, whilst our new site was under construction, our current site at the time got hacked. The hack seemed to replace pages with Japanese site alternatives.

It seems now that the issue is mainly sorted (Checked on Google Webmaster Tools and followed through the steps of registering as not being hacked, as well as updating sitemaps etc.)

The problem I am having now is that links are still being indexed on Google, and other search engines, with Japanese titles and are producing 404 Page Not Found errors.

See site:justaccounts.com in Google.

I want to removed these from being indexed as we are receiving a lot of crawl errors and a very high bounce rate because of this.

Is it possible to have any new 404 errors we produce be automatically changed to a 410 so Google will un-index it quicker? Doing this for every page manually would be quite a task as we have hundreds of these coming through.

If not, do you have any suggestions on helping with this issue as I want to start looking at reducing the bounce rate and the amount of traffic that comes from Japan.

Thank you in advance!