[Ekiga-list] How to call each other using ekiga.net account

[zhu shi song <zhushisongzhu yahoo com>]

Hi,
    I have registered two accounts as zhuzhonghua ekiga net and szjm ekiga net seperately。I hope to call each other to test .  But I can't call another account using one.  The error is "user is not online".  

    I connect internet through one NAT router.    Maybe my network set is wrong.  Who can me more hints?

    thanks
   zhu