I ran a test order through my Zen Cart and after I submitted the PayPal payment I recieved this error:

1054 Unknown column 'zen_order_id' in 'where clause'
in:
[select * from paypal where zen_order_id = '2' order by paypal_ipn_id DESC LIMIT 1]

I was not returned back to my site but instead got an error message. The order is in the Admin tool and it was actually paid for but I never was returned to the site.

Does anyone know what this is and how to correct it?