Fix sending ACK on Invite OK (last attempt to revert libs do nothing)

src/net/java/sip/communicator/impl/protocol/sip/OperationSetBasicTelephonySipImpl.java

@@ -658,7 +658,8 @@ private void processInviteOK(ClientTransaction clientTransaction,
         {
             //Need to use dialog generated ACKs so that the remote UA core
             //sees them - Fixed by M.Ranganathan
-            ack = clientTransaction.getDialog().createRequest(Request.ACK);
+            CSeqHeader cseq = ((CSeqHeader)ok.getHeader(CSeqHeader.NAME));
+            ack = clientTransaction.getDialog().createAck(cseq.getSeqNumber());
 
             //Content should it be necessary.
 
@@ -677,6 +678,15 @@ private void processInviteOK(ClientTransaction clientTransaction,
                 "Failed to create a content type header for the ACK request"
                 , ex);
         }
+        catch (InvalidArgumentException ex)
+        {
+            //Shouldn't happen
+            callParticipant.setState(CallParticipantState.FAILED
+                , "Failed ACK request, problem with the supplied cseq");
+            logger.error(
+                "Failed ACK request, problem with the supplied cseq"
+                , ex);
+        }
         catch (SipException ex)
         {
             logger.error("Failed to create ACK request!", ex);