[SR-Users] Fwd: ACK issue TCP in NATed network

Hello Everyone, We are using Kamailio IMS (version 5.0.4). We are using Jitsi for making calls. Our SIP clients are behind NATed network. When clients and P-Server is configured to UDP mode, we are able to make calls sucessfully. When clients and P-Server is configured to TCP mode, call is not getting through. From logs I found that ACK is not being sent from P-Server to Client. On googling i found that this is known problem. Can anyone kindly clarify whether this problem is resolved? Is there is work around. Am i not setting any parameter properly? Let us know if further information is needed. Kindly some answer, we are newbies... :) Regards GS Kumar