Random items added to basket at checkout?

["kyle@invisio.com" <kyle@invisio.com>]

Has anyone else ever seen items appear in the
receipt page when they were not ordered (at least 
according to the customer)?

I have a customers shop (running mv 3.11) that has
been up for 6 months and has handled apx 1,000
orders so far but recently a couple of orders were
placed and the customers swear they did not order 
one of the items listed in the basket page, yet
everything else looked fine?

I've dumped the session.db file and looked through
it and could not find any problems, it looked as though
the items were added to the basket by the customers!


Thanks,
Kyle Cook (KC)

PS I tried the archives, but it is difficult to pick out a
keyword or phrase to search for on this one.