[h323plus] Changing video codec transmit bit rate

Hi all, How would one go about adjusting the video codec max transmission bit rate? I understand thus can be done in OpenVideoChannel by calling codec.SetMaxBitRate but I I get no flow control supported when I attempted to do so. I am using v 1.23 for H323plus downloaded from h323plus.org and pitlib v 2.8.5. I noticed that flow control is not supported in ptlib less than 2.9 but would there be another way of changing the bit rate? Thanks! Josh C.