memcpy( nm->header, omhdr, sizeof( char ) * (old_psize + RMR_HDR_LEN( omhdr )) );
if( DEBUG ) rmr_vlog( RMR_VL_DEBUG, "rmr_realloc_payload: copy payload into new message: %d bytes\n", old_psize );
} else { // just need to copy header
memcpy( nm->header, omhdr, sizeof( char ) * (old_psize + RMR_HDR_LEN( omhdr )) );
if( DEBUG ) rmr_vlog( RMR_VL_DEBUG, "rmr_realloc_payload: copy payload into new message: %d bytes\n", old_psize );
} else { // just need to copy header