This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
I don't know anything about your business owner's requirement, but we use JMS queues as a step when sending emails because the queue guarantees delivery and the message is not deleted from the queue until the consumer acknowledges that the email was sent successfully. Messages can be "sent" (queued) even if the email send process is offline.
If you have an email failure, like if the network is unavailable or the email gateway goes down, how do you propose to handle it?