Categories give 404 after upgrading to 1.5.6

[ivanomino]

Hi, after upgrading prestashop to 1.5.6, categories doesn't works fine - now i get a 404 on categories link. If i try to use istant search, products appears in categories and subcategories, but categories link not appear in breadcrumb. I tried to insert categories again manually, but System doesn't allow to insert subcategories. All categories are inserted at same level of root.  It seems that Prestashop categories doesn't works fine. Please check it - www.ilovesicily.ie