Sortable: 'update' doesn't fire when last item from one list is moved to beginning of other

Sortable: 'update' doesn't fire when last item from one list is moved to beginning of other


Example: http://www.justinstayton.com/sortableTest.html
There are two sortable lists: #row1 with two items (#1 and #2), and
#row2 with one item (#3). I have 'update' writing the row 'id' and
sortable('toArray') to the console.log, so watch for it in Firefox/
Firebug.
If you move #3 from #row2 to the end of #row1, or in between #1 and
#2, 'update' gets fired twice -- once for the row it's leaving and
once for the row it's going to -- as expected. The console.log should
look like this:
row2
[]
row1
["1", "3", "2"]
However, if you move #3 from #row2 to the beginning of #row1, 'update'
only gets fired once for the row it's going to:
row1
["3", "1", "2"]
Is this working as it should, or is this a bug? Thanks for any help.
Justin