Time Machine 2tb limit?

Hi,
I'm considering turning on Time Machine support in the ReadyNAS, setting it to the maximum size it allows (4085 GB), creating a sparsebundle image larger than that with htutil and then copying it over to the ReadyNAS.

I know that sparsebundle images can be created with htutil well above the TB range, into the peta and exa-byte ranges (http://developer.apple.com/mac/library/ ... til.1.html) so it is not an issue with sparsebundles. Likewise, I know that TimeMachine can backup to volumes larger than 4TB (e.g. 8 bay Drobo with 2 TB drives works fine).

So, this is again an issue with the ReadyNAS Pro.

Anyone see any issues with creating a backup this way or have a better solution?

e.g. should I just turn off the ReadyNAS support, create the sparse bundle there and use it that way?

Thanks for any insight.