British Expats - Telephones

Sorry, I know this topic has come up before but I never did work out what the definitive answer was. :confused:

We are debating whether to take our BT cordless digital phones to WA with us, but I have heard and seen various comments to suggest their use would be illegal because of the frequency interference. We also have a BT analogue corded phone I would like to take with us - are these compatible with the Oz telecoms system, or would it be illegal to use that too?

We have told both lots of shippers' reps that we intended taking them, and neither said that we wouldn't be able to do so.

Can anyone set me straight once and for all please?

TIA.