Spark Conection over VPN does not work with Openfire under Linux

Version 1

    I have two Openfire Server instaledd on my network :


    server 1 - installed on a windows 2003 machine with openfire default DB

    server 2 - installed on a centos 5.3 machine with a mysql DB


    I have a Home location and a Remote location conected through a vpn; the computers at remote location act as they would be in the local LAN; the take their IP throught DHCP; can browse the network..etc


    At remote location if I try to connect spark at server 1 it works perfectly, but if i try to connect at server 2 i get the message Invalid Username or Password ?


    What can be the problem ?