There seems to be a problem getting the list of subscribers of a pubsub node. getSubscriptions only returns the list of subscriptions for the current user, where as the spec says it should return all users that are subscribed to the node.
As per XEP-0060 "XEP-0060: Publish-Subscribe" the request namespace should be "http://jabber.org/protocol/pubsub#owner" where as the request sent by smack is "http://jabber.org/protocol/pubsub"
REQUEST:
<iq to='pubsub.localhost' id='WAI96-13' type='get'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<subscriptions node='test'/>
</pubsub>
</iq>
RESPONSE:
<iq from='pubsub.localhost' to='chaits@localhost/Smack' id='WAI96-13' type='result'>
<pubsub xmlns='http://jabber.org/protocol/pubsub'>
<subscriptions>
<subscription jid='chaits@localhost/Smack' subid='58C18F8917321' subscription='subscribed'/>
</subscriptions>
</pubsub>
</iq>
I noticed this in 4.0.6 and also 4.1.0-alpha6.