open_basedir "/" not working after upgrade

Hello all... I just upgrade PHP from version 4.3.4 to version 4.3.8. After the upgrade, almost everything worked fine but the open_basedir directive. The server I administer provides hosting for several domains, all of those with its own homedir restricted using open_basedir <domainhome> in a <Virtualhost> scope. Some especial directories, for example the webmail directory, is there only one, but it is shared by all the virtualhosts (http://<virtualhost>/webmail/). I achieve that using (en httpd.conf): Alias /webmail "/apache2/htdocs/horde/imp" <Directory /apache2/htdocs/horde > php_admin_flag safe_mode off php_admin_value upload_tmp_dir /tmp php_admin_value open_basedir "/" </Directory> This worked fine until the upgrade. After it, I get a message claiming that the open_basedir directive is in use, and that "/apache2/htdocs/horde/imp" is not in (/). I guess this could be an error in the open_basedir implementation (or just a change), but I am not sure. What I saw is that in recent version there were a lot of "move" around open_basedir code. Can anybody help me with this? is there any patch I could apply to solve this? Thank you!