Thanks a lot !! Has been really userfull !
I also had a problem with the login form. When I used the login form, it always redirected me on the main page of the forum but always in the main language.
Te solve this problem, just modify another line in bbpress/includes/common/template.php on line 1181 :
On line 1181, replace:
$redirect_to = ( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI'];
with:
$redirect_to = qtrans_convertURL(( is_ssl() ? 'https://' : 'http://' ) . $_SERVER['HTTP_HOST'] . $_SERVER['REQUEST_URI']);