asterisk users - Oct 2004 - OH323 and Mera Softswitch

When I am trying to connect Mera Softswitch MVTS (www.meravoip.com) ,
I get the following error :


OH323/L31774 is ringing
Oct 11 17:13:26 WARNING[573459]: chan_oh323.c:1039 oh323_exception:
OH323/L31774: Invalid format of RTP addresses.
    -- OH323/L31774 answered SIP/2001-6c5e


No sound on aany side.

Ehsanul Karim