Add Email Alerts to existing PHP/MySQL Website for Unsent SMS

Overview - I have an existing website/system built on the WAMP platform using the Codeigniter framework (with Grocery_CRUD), that allows customers to make bookings for couriers to pickup goods, and the website/system will then automatically send an SMS to a courier with the pickup details. Summary - Currently if an SMS cannot be sent due to an issue with the SMS gateway or issues with the customers contact details etc, the website/system will try to send the SMS once only and if it fails to send it will move the SMS to the Unsent Message Queue but not notify anyone. What I require is either: 1) A program or application or modification to the existing website/system that will check the existing SMS Unsent queue periodically (e.g. every 5mins) and then send an email to multiple email addresses if an SMS appears in the Unsent queue. OR 2) A modification to the existing website/system that will send an email to multiple email addresses as soon as an SMS message is being moved to the unsent queue. NOTES - A) Any solutions are to be written/developed in a similar way to the rest of the website/system. The website/system has been developed using Codeignitor and Grocery_CRUD which should be used if modifying existing modules/files however I am OK if any new functionality is created/written in PHP. B) Code should include comments in English where practical and not be encrypted. C) Both the 'SMS Unsent' and 'SMS Sent' Queues exist in the MySQL database the website/system uses. D) The SMS functionality - that exists between the website/system & the SMS Gateway - is controlled by a custom written Java application that uses GSMComm v1.21 E) I don't think that any modifications will be required to the SMS functionality as it will probably be a straightforward MySQL Database and PHP coding solution - refer item 'C' above F) System Details - WAMP Server 2.2 Apache v2.2.21 MySQL v5.5.20 PHP v5.3.9 Codeigniter v2.1.0 Grocery_CRUD v1.1.7 GSMComm v1.21 Windows Server 2008R2 64bit