not sure if there is a particular reason why you have to have page/subpage as you cannot specify the / character for your page url. What you could do is use the hyphen so you could have www.mysite.com/page-subpage1 and www.mysite.com/page-subpage2 if you wanted and this fullfilled your needs.
I've just started using Silverstripe and I am currently still evaluating it to see if it fit my needs. I really like this CMS and hope I will be able to use it for my project which is quite large.
One function I need is to be able to create URL's like http://www.mysite.com/sweden/stockholm/about/subject/
This is very important for me, as if it is not possible, I'm afraid I have to find another CMS.
I found some good news at http://www.silverstripe.com/up-and-coming-features-aug2008/ about the new improved URL handler.
I installed the trunk silverstripe.2.0.DailyBuild.2008-09-04.tar.gz but can't figure out how to implement the new URL handler.
Is the new URL handler included in this DailyBuild? and if so how do I activate it?
This feature isn't in the daily builds. That blog post only meant there is a new URL handler that will make implementing sub-level URLs for pages easier. This means that what you're after isn't quite possible at this point in time.
May I ask what your reason is for having this feature?