In Israel, what do you do if Isru Chag of Pesach is on Shabbat?

For example this year (2012, 5772):  
The last day of Pesach is on a Friday, and Isru Chag (the day after the holiday) is on Shabbat.

When do people reacquire their chametz that they sold on Pesach?

Do they acquire it retroactively after the holiday is over, so they **can** eat their chametz that shabbat, OR do they not acquire it until after Shabbat is over, so they have to not eat chametz an extra day?

I know of this question: http://judaism.stackexchange.com/q/14263/719, but my question here involves chametz that is one's own house and was sold over Pesach.