I used to be able to send email using the simple mail() in PHP although since I have upgraded to the latest PHP I am unable to send emails. 

When I look at the email log I get the following:

```
Jun 29 21:14:49 Johns-MacBook postfix/pickup[26503]: 384B6246803: uid=70 from=<_www>
Jun 29 21:14:49 Johns-MacBook postfix/master[26709]: fatal: open lock file pid/master.pid: unable to set exclusive lock: Resource temporarily unavailable
Jun 29 21:14:49 Johns-MacBook postfix/cleanup[26680]: 384B6246803: message-id=<20110629201449.384B6246803@example.com>
Jun 29 21:14:49 Johns-MacBook postfix/qmgr[26504]: 384B6246803: from=<_www@example.com>, size=351, nrcpt=1 (queue active)
Jun 29 21:14:49 Johns-MacBook postfix/local[26683]: 384B6246803: to=<ben@example.com>, relay=local, delay=0.02, delays=0.01/0/0/0, dsn=5.1.1, status=bounced (unknown user: "ben")
Jun 29 21:14:49 Johns-MacBook postfix/cleanup[26680]: 3C318246805: message-id=<20110629201449.3C318246805@example.com>
Jun 29 21:14:49 Johns-MacBook postfix/qmgr[26504]: 3C318246805: from=<>, size=2033, nrcpt=1 (queue active)
Jun 29 21:14:49 Johns-MacBook postfix/bounce[26684]: 384B6246803: sender non-delivery notification: 3C318246805
Jun 29 21:14:49 Johns-MacBook postfix/qmgr[26504]: 384B6246803: removed
Jun 29 21:14:49 Johns-MacBook postfix/local[26683]: 3C318246805: to=<_www@example.com>, relay=local, delay=0, delays=0/0/0/0, dsn=2.0.0, status=sent (delivered to mailbox)
Jun 29 21:14:49 Johns-MacBook postfix/qmgr[26504]: 3C318246805: removed

```