There were two forks 195k and 197k. When fixed, old versions will follow the true chain. ...currently working on it.
feel free borrowing from diamond code the solution
u have to make new wallet ban old wallets when they try establish peer connection
we had much troubles with old wallets to and that solved it
we do it based on the wallet subver
active it look like that in debug log
07/11/14 19:17:38 accepted connection 72.78.100.2:40751
07/11/14 19:17:38 received: version (100 bytes)
07/11/14 19:17:38 connected subver /Diamond:2.0.1/
07/11/14 19:17:38 partner 72.78.100.2:40751 using obsolete client /Diamond:2.0.1/
07/11/14 19:17:38 ProcessMessage(version, 100 bytes) FAILED
07/11/14 19:17:38 disconnecting node 72.78.100.2:40751