having trouble with s2s people cannot join my servers conference

hi there i would like to know how i can fix this problem. i can join other server rooms. but other servers cannot join mine.
here is some console stuff lol

=INFO REPORT==== 2012-01-01 23:22:44 ===
I(<0.402.0>:ejabberd_s2s:369) : New s2s connection started <0.412.0>

=INFO REPORT==== 2012-01-01 23:22:44 ===
I(<0.412.0>:ejabberd_s2s_out:1203) : Trying to open s2s connection: jabberuk.dyndns.org -> talkonaut.com with TLS=false

=INFO REPORT==== 2012-01-01 23:22:44 ===
I(<0.404.0>:ejabberd_c2s:785) : ({socket_state,tls,{tlssock,#Port<0.455>,#Port<0.457>},<0.403.0>}) Accepted authentication for marcus by []

=INFO REPORT==== 2012-01-01 23:22:44 ===
I(<0.392.0>:ejabberd_listener:281) : (#Port<0.475>) Accepted connection {{74,123,227,230},64031} -> {{192,168,1,67},5269}

=INFO REPORT==== 2012-01-01 23:22:44 ===
I(<0.404.0>:ejabberd_c2s:938) : ({socket_state,tls,{tlssock,#Port<0.455>,#Port<0.457>},<0.403.0>}) Opened session for marcus@jabberuk.dyndns.org/Gajim

=INFO REPORT==== 2012-01-01 23:22:44 ===
I(<0.392.0>:ejabberd_listener:281) : (#Port<0.480>) Accepted connection {{74,123,227,230},64034} -> {{192,168,1,67},5269}

=INFO REPORT==== 2012-01-01 23:22:45 ===
I(<0.406.0>:ejabberd_s2s_out:365) : Connection established: jabberuk.dyndns.org -> conference.talkonaut.com with TLS=false

=INFO REPORT==== 2012-01-01 23:22:45 ===
I(<0.412.0>:ejabberd_s2s_out:365) : Connection established: jabberuk.dyndns.org -> talkonaut.com with TLS=false

=INFO REPORT==== 2012-01-01 23:22:54 ===
I(<0.411.0>:ejabberd_s2s_out:235) : s2s connection: jabberuk.dyndns.org -> conference.jabberzoneprogramming.dyndns.org (remote server not found)

=INFO REPORT==== 2012-01-01 23:23:06 ===
I(<0.411.0>:ejabberd_s2s_out:887) : Reconnect delay expired: Will now retry to connect to conference.jabberzoneprogramming.dyndns.org when needed

what do i do to fix this error?