How do I eliminate a webform error?

I've created a webform for our Singing Valentines program, and it appears to be working successfully so far.  The only glitch we are experiencing is an error that appears at the top of the custom confirmaton page once an order has been submitted. 
warning: array_filter() expects parameter 1 to be array, string given in /home/groupanizer/domains/gsing_na1/prod/sites/all/modules/webform_validation/webform_validation.validators.inc on line 435.
It doesn't appear to be causing any problems with the data, as I am getting the emails just fine and the data is appearing in the results area of the webform.  It is just a little unnerving to a couple of customers, as they have followed up their orders with a phone call to make sure we really got their order. 
So I'm wondering if any of our more experienced users recognizes what this error means, and what should I do to correct the problem?
Thanks again for any help.  This forum has been a wonderful resource as we get our soon to be public website up and running.  Check us out and send feedback as warranted.