In reply to:
So, It would need 2 IPs, yes? and from 2 different ranges?
I haven't done it on an 834 so don't want to be too definitive

My 834s have 3rd party firmware on.
On a Billion router, and a USR9105, I used a facility they have to assign a second IP address to the LAN side and put a second public address on there. I then had a mix of private and public IPs on the LAN and was able to access the public IP machines from inside and out. The WAN side IP of the router was from the same IP block as the LAN side but a different address. This is similar to what you are doing, except I have a single IP block.
The approach advocated by Entanet resellers is I think that you have a block of IPs and that you either put the same address on the LAN side as on the WAN side or don't bother - Zen say something similar at
http://www.zensupport.co.uk/knowledgebase/article.aspx?id=10048 for a /29 block.
Phil
666 kbytes/s with Demon
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