Xen and memory beyond 2GB?

[Johan Ihrén <johani%autonomica.se@localhost>]

I have interests similar to Marrti Kuparinen's in that I'd like to be 
able to run a substantial number of virtual machines (at least a dozen) 
on the same box and the aggregated memory requirements will exceed 2GB. 
The memory reuirements of each VM will be below 2GB though.

For this to work, is it necessary to have a "64bit" box, i.e. an Intel 
EM64T or AMD64 where I can address all the memory from a single 
userspace process or is it sufficient with a std i386 as long as the 
motherboard has an MMU capable of addressing more memory?

In the latter case I realise the limitation to 2GB *per process*, but 
that might be ok (as the individual VMs will be smaller than that) 
depending on how xen works.

Any insights?

Regards,

Johan Ihrén