[Dovecot] doveadm director map : User listing returned failure

Hello we are running Dovecot 2.1.9. We have 2 proxies with director and 4 mail servers. We have the user information in a LDAP.

I try to do: # doveadm director map doveadm(root): Error: User listing returned failure doveadm(root): Error: user listing failed user mail server ip expire time
<unknown> x.x.x.x 2012-09-12 10:52:17 <unknown> x.x.x.x 2012-09-12 10:55:53

in the dovecot log i have found:

dovecot: auth: Error: Trying to iterate users, but userdbs don't support it

What can I do to solve this problem? Thanks in advance.

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Ramon Frontera Gallardo Universitat de les Illes Balears