A bit of history
Joomla 1.0 allowed two or more user accounts to use the same email address. It did not enforce address uniqueness.
This functionality was lost in subsequent Joomla releases. Many community groups were very disappointed and the Joomla forums are still filled with requests and hack attempts to get this functionality back.
The use case need
For many different reasons there are many people that do not have, or are unable to cope with, their own email address. Examples include senior citizens, disabled, children, infants, etc.
In many cases someone physically supports such individuals by either:
- Creating and managing an email address for them. E.g., A son creates and monitors an email address for his grandfather.
- Allowing them to use an existing email address. E.g., A father submitting his email address on a website his under aged daughter wants to join (e.g., Barbie website).
As you can imagine Joomla websites that want to support use cases that include such “cannot handle my own email” people have a problem. There are many website use cases that are affected. The two (2) largest groups are: church sites and children sites.
There is no need to hack and there is no need to create multiple email accounts either.
You can use the “not so known” email sub-addressing feature that is supported by most email servers (gmail, hotmail, etc.).
How does it work?
Let's say you have an email address email@example.com. With email sub-addressing the following email addresses are valid and of course unique for Joomla:
Any email sent to one of the above addresses will be delivered to the firstname.lastname@example.org account but the to: address will retain the +tag part (so the email manager knows which tag was used).
Try it - it works and provides a great service for many communities that want to use Joomla for their websites and have hit the unique email address wall.
Note that some email servers use a ‘-‘ symbol instead of a ‘+’ symbol as the tag delimiter. More about email and address tagging can be found on wikipedia.
Other uses for this trick
I also use this method when registering on various websites that require an email address. If I use my normal email address to register on such websites, after a while I am forced to go through tons of emails that do not really interest me.
So, I use this trick and register on each website using the address email@example.com, firstname.lastname@example.org, etc.
I then just create a nice auto-filter in my email client that automatically moves such mailings to different folders. This way my main inbox if free and I can inspect or remove contents of these other folders whenever I have time.