multi site wordpress - domain mapping - getting "Apache is functioning normally"

hi
i cant get the domain mapping to work.. i did everything like in the manual.
-i have a vps with dedicated ip
-direct admin panel
-subfolders multi site
-domain mapped with NS
-domain ping return server ip
-adding new site, mapping the domain through the plugin, no response, when i go to the url i get "Apache is functioning normally".

what am i doing worng?
thanks