/ro missing after www.domain.ro

[Rhobur]

I have a big problem with URL in 1.4.0.17, don't know if it's my fault or something else; I
m getting a lot of not found pages because I'm missing the /ro after the domain name. For example the existing
http://www.caprice-shop.ro/content/5-plati-sigure is redirecting to http://www.caprice-shop.ro/ro/content/5-plati-sigure which is not found. Not to mention that a lot of other not founds have /lang-ro in URL instead of /ro .
Can anyone suggest anything ?

EDIT: I have deactivated the Tomerg's DuplicateURL module and now the redirection to /ro doesn't happens anymore but is this the right way ? Tomerg says that it is mandatory in 1.4.0.17 to have URL's like www.domain.ro/ro/ and not like mine's www.domain.ro .