replication DBT size

Hello.

Is it any way to set upper limit (in bytes) for data send by transport
infrastructure (maximum number of bytes callback function, set by
set_rep_transport, can send) in replication subsystem. Or may be it is
some DB internal limits on control and record DBT size. May be I
misunderstand some concepts, but we are going to use datagram sockets, and
it is important for us to receive DBT data (control and rec send by f_send) in one
datagram. Also it is important not to use dynamic heap memory allocation
for incoming data, but predefined buffer.

BDB version 4.2.50

Best regards.