Error message

• Warning: array_flip() [function.array-flip]: Can only flip STRING and INTEGER values! in DrupalDefaultEntityController->load() (line 178 of /home/sfetcu/public_html/sfetcu.com/includes/entity.inc).
• Warning: array_flip() [function.array-flip]: Can only flip STRING and INTEGER values! in DrupalDefaultEntityController->cacheGet() (line 354 of /home/sfetcu/public_html/sfetcu.com/includes/entity.inc).