help with routes[]

[eluser]chefnelone[/eluser]
Hello

I have this route rule working fine:

Code:

$route['[^/]+/(:any)'] = 'index/$1';

it re-maps these URL strings:
en/photos
es/contact
cat/contact

but my problem is that it re-maps these too:
something/photos
somethingelse/contact

I need to limit the rule to work only if the first segment have 2 o 3 characters.
I know I have to put {2,3} somewhere but don't know where....

thanks