Bug? AdHoc-Commands (Psi / Gajim)

I tried out AdHoc-Commands on my Openfire-Server (v3.3.1). Among other things I tried “get-group-members”. After entering the Name of the Group (“Test”, existing), I got as result only an empty window with an “ok”-button. First I thought it would be a problem with Psi (because it is only an RC) but Gajim has the same problem. So found a Bug?

(Clients used: Psi 0.11-RC1 and Gajim 0.11.1-1.fc6)

<iq type="set" to="test-jabber.dyndns.org" id="aaefa" >
<command xmlns="http://jabber.org/protocol/commands" node="http://jabber.org/protocol/admin#get-group-members" />
</iq>
<iq from="test-jabber.dyndns.org" type="result" id="aaefa" to="admin@test-jabber.dyndns.org/dothan" >
<command xmlns="http://jabber.org/protocol/commands" status="executing" node="http://jabber.org/protocol/admin#get-group-members" sessionid="cN7eOa7LTp7VV1V" >
<x xmlns="jabber:x:data" type="form" >
<title>Requesting List of Group Members</title>
<instructions>Fill out this form to request list of group members and admins.</instructions>
<field type="hidden" var="FORM_TYPE" >
<value>http://jabber.org/protocol/admin</value>
</field>
<field type="text-single" label="Group Name" var="group" >
<required/>
</field>
</x>
<actions execute="complete" >
<complete/>
</actions>
</command>
</iq>
<iq type="set" to="test-jabber.dyndns.org" id="aaf0a" >
<command xmlns="http://jabber.org/protocol/commands" node="http://jabber.org/protocol/admin#get-group-members" sessionid="cN7eOa7LTp7VV1V" >
<x xmlns="jabber:x:data" type="submit" >
<field type="hidden" var="FORM_TYPE" >
<value>http://jabber.org/protocol/admin</value>
</field>
<field type="text-single" var="group" >
<value>Test</value>
</field>
</x>
</command>
</iq>
<iq from="test-jabber.dyndns.org" type="result" id="aaf0a" to="admin@test-jabber.dyndns.org/dothan" >
<command xmlns="http://jabber.org/protocol/commands" status="completed" node="http://jabber.org/protocol/admin#get-group-members" sessionid="cN7eOa7LTp7VV1V" >
<x xmlns="jabber:x:data" type="result" >
<reported>
<field type="jid-single" label="User" var="jid" />
<field type="boolean" label="Description" var="admin" />
</reported>
<item>
<field var="admin" >
<value>0</value>
</field>
<field var="jid" >
<value>user1@test-jabber.dyndns.org</value>
</field>
</item>
<item>
<field var="admin" >
<value>1</value>
</field>
<field var="jid" >
<value>foobar@test-jabber.dyndns.org</value>
</field>
</item>
</x>
</command>
</iq>