Is there a way to create a SEF URL prefix to simulate language code?

for example, instead of having a URL display as:
www.site.com/aboutus.html

it will appear as
www.site.com/en/aboutus.html
on English site

Our new site is will be using JoomSEF3, but not Joomfish (like current site) and we would like to preserve legacy SEF URLs when it goes live.

I have tried changing the settings in the content extension, specifically Content -> Custom -> Menu Titles, but it doesn't seem to be doing the trick.

Any suggestions would be appreciated!

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order# 12423

Hello,

Unfortunately, this is not possible with JoomSEF at the moment, but thank you for your suggestion, we'll add this to our requested features list.

Best regards,
ARTIO Support Team

Is there any way to add a prefix (besides the stock category or section) to the URL? There has got to be a clever way to do this.

This would require a modification in JoomSEF's source code. Or you could probably create the "en" subdirectory on your web server and move your whole website there, but that's not really nice at all.
Or maybe you could create a redirection rule in your .htaccess file that would redirect every URL starting with /en/ to its new version without the prefix.

Best regards,
ARTIO Support Team