max number of subnets/addresses?

I've been asked a couple of questions by our engineering guys.

1) Is there any inherent limit on the number of IP addresses that can be configured on an interface?

2) Is there any inherent limit on the number of subnets that a linux host can have configured at any given time?

If anyone could answer these off the top of their head, it would save me some time digging through unfamiliar code.

Thanks,

Chris