A PHP5 port of the Mail_Queue package.
The API is very similar except for:
- PHP 5.3 minimum (
new \PEAR2\Mail\Queue(...);) - visibility of all methods is enforced
 - no dependency on PEAR
 - throws exceptions in most cases
 - non-fatal error are still with 
hasErrors()andgetErrors() 
Until I get to PEAR2, just use composer.
- add a container for Doctrine2 (ORM or DBAL?)
 - add support for Swiftmailer
 - investigate better queues than RDBMS