asort has one anoying feature, it ignores any default or implicit order in the data. i.e. if two elements of an array contain "banana" then it is not garanteed that the first will still be the first after the sort.
This makes the Burrows-Wheeler block sort a bit of a pain to impliment, with a trailing string having to be appended to all strings before sorting, and removed after sorting. To maintain the so called "banana" order.