There is a vine called Clematis microphylla which grows to 5mt. high, but will ramble across other plants. It sets seed from Nov-Dec., very feathery and fluffy.
Cheers,
Dee.

Thanks very much for that Dee,
it certainly sounds like the one I saw,
Cheers, Yvonne

Leaves and seeds are wrong for microphylla, that has three pointed leaves and much finer seeds. It might be Clematis aristata, but I suspect from the location it is a garden escapee.

Was there a photo with your posting Yvonne? I can't see one and there wasn't one there yesterday either. I went purely on description. Obviously Nathan can see something I can't. How can that be?
Cheers,
Dee.

I look at the source and I see:
href="http://img156.imageshack.us/my.php?image=copyof10021420bg.jpg";
src="http://img156.imageshack.us/img156/2789/copyof10021420bg.th.jpg";

Here is a link that might be useful: {{gwi:2116825}}

Thanks Nathan. It certainly does help when one has a picture to work with! I appreciate your help.
Yvonne, I agree with Nathan that it is not Clematis microphylla. C. microphylla does grow on the Mornington Peninsula, but this one isn't it. It is not fluffy enough to start with. It is a Clematis but I'm not sure which one. A picture of the flower would help. Maybe next season?
Cheers,
Dee.

I think it is Clematis vitalba (Traveller's Joy), a common invasive weed.