I get the following error code:

user error: You have an error in your SQL syntax near 'ON n.nid = a.nid WHERE n.nid = 56' at line 1
query: SELECT a.* FROM amazonnode a JOIN node n ON n.nid = a.nid WHERE n.nid = 56 in /home/virtual/xxx/fst/var/www/html/xxx/includes/database.mysql.inc on line 66.

When I browse to the edit page for the Amazon Node type.