Horde LDAP errors

[Price,Neil]

I'm seeing the following in my horde log file:

HORDE [error] [horde] Internal LDAP error.  Details have been logged for
the administrator. [pid 20612 on line 337 of
"/usr/share/horde3/lib/Horde/Prefs/ldap.php"]
HORDE [error] [horde] Zero or more than one DN returned from search;
unable to determine user's correct DN

I don't see see any corresponding errors in the ldap log (unless I have
not enabled the correct log level)

Horde version is 3.3 with Kolab 2.20 (Debian port). Test.php shows I have
pecl'd all my pears correctly.

Horde still seems to work but does not retrieve Kolab user info (I'm not
sure if its supposed to. I checked the search dn and the password are
correct (phppw)

Any pointers?