Strange olcDbDirectory permission error

[Ian Collins <ian@ianshome.com>]

 Hello,

I'm in the process of copying a server configuration to an Ubuntu server 
and I'm getting a very strange error on start up:

Jul  7 14:46:03 Ubuntu64 slapd[5079]: config error processing 
olcDatabase={1}hdb,cn=config: olcDbDirectory: value #0: invalid path: 
Permission denied

strace shows:

[pid  5079] open("/opt/local/var/run/openldap//DUMMY", 
O_WRONLY|O_CREAT|O_TRUNC, 0666) = -1 EACCES (Permission denied)

Even with the directory writeable to all:

drwxrwxrwx 2 openldap openldap 4096 2011-07-07 14:29 
/opt/local/var/run/openldap/

Any ideas?

--
Ian.