Error getting UID/GID

I have just moved my mail system into a jail but now in vexim I am 
getting Error getting UID/GID when I try and add a domain
My  settings in variables.php are

 $uid = "1000";
 $gid = "1000";
which is correct for the user

all the existing email accounts are follow fine and i can add new users 
no problem just adding domains gives the error
Tried a clean install of vexim php files too

Pretty sure this is a jail problem. Just tried lighttpd instead of 
apache and used 
http://www.schirmacher.de/display/INFO/improved+Vexim+frontend+and+bug+fixes  
just in case and still the same error

7.1-RELEASE FreeBSD
 php -version
PHP 5.2.8 (cli) (built: Feb 20 2009 17:12:38)