Why does the first page of one category redirect to empty page 4?

I really hate the wp-e-commerce plugin.

It turns out that the only products in that category were ‘pending’, i.e. not published yet. Even if they were moved to trash, and ‘hide_emtpy => 1’ was used on the categories list, the error still occurred.

Only when the products were completely emptied out of the trash did the category disappear from the menu, and the problem was resolved that way.

The reason it forwarded to page 4 is still unknown.