SSM1/SSM2 protocol change.. When, How?

[Impakt]

Hi all,
I noticed that there is an older version of the protocol (the one that uses ~1953bps), as shown on www.scoobymonitor.co.uk , but you guys seem to concentrate on the newer protocol. So i'm guessing that ~1998 Subaru changed from this 1953bps protocol to SSMII (4800bps).

Can anyone confirm that when the protocol changed the hardware required to talk to the ECUs also changed from the simple MAX232 based circuits to ISO9141 based circuits?

A friend noted that the MY98 WRX sold in australia has the old style select connector, but works with his select II monitor. So does this vehicle use the 4800bps protocol with the old plug? Does it work with the ISO9141 based circuit?

Thanks!
Daren