I know nothing about Hotmail as it is one of the few email services I don’t have an account for, but it seems that those outside the U.S. are not eligible for the upgrade to 250 MB. However, Sergio at Overcaffeinated.net has posted a tip for non-USers looking to upgrade their inbox.

If you want to upgrade your miserable 2MB Hotmail Inbox to 250 Mb and you’re not from the US, change your profile info to a US State (I used “Florida”, Zip 33332), then go to passport.net, and in “Member Services”, close your .NET account. Click through all the warnings [...], finish the process, go back to the hotmail site, re-login (by this point your account has been put “on hold”) to reactivate your account (you’ll have to re-do the end user agreement and stuff) and voila. Your account will have a 25 Mb Inbox. Give it up to a month for the 250 Mb upgrade, which will happen automagically.