Hi JavaBean
On the BT Versatility it is correct that you would require RJ-45 telephone adaptors (sometimes referred to as OSCA ADAPTOR) to be able to plug telephones into a structured cabling outlet.
The part about digital and analogue adaptors is incorrect, the extensions on a BT Versatility are analogue (regardless of whether the system has digital or analogue lines). In order to connect any of the devices mentioned you would need a PABX Mastered adaptor for each device (fax machine, PDQ or V Phone) as mentioned below.
You would not require an analogue card, the analogue card would only be required if you want to connect analogue (or PSTN) lines to the system.
In summary,
A) No you don’t.
B) PABX Mastered.
Hope this helps
Tracey