XMPP4R and Openfire

My app sends IM with XMPP4R with Jabber accounts perfectly with this code, but when I want to use an Openfire problem I get an error of authorization

    jid = Jabber::JID.new('myuser@example.com')     @client = Jabber::Client.new(jid)     @client.connect     @client.auth('xxxxxx')

The error: /Library/Ruby/Gems/1.8/gems/xmpp4r-0.4/lib/xmpp4r/client.rb:116:in `auth': not-authorized (Jabber::ClientAuthenticationFailure) ...

I didn't find any solution searching in Google, yet. Where can I find a tutorial, howto??? You know what is the problem?

Thanks in advance!