我正在使用PHP内置的mail（）函数：
mail("test@gmail.com", "test", "hello");
我的PHP.ini设置如下：
[mail function]
; For Win32 only.
; http://php.net/smtp
SMTP = localhost
;smtp_server = localhost
; http://php.net/smtp-port
smtp_port = 25
; For Win32 only.
; http://php.net/sendmail-from
;sendmail_from = me@example.com
; For Unix only. You may supply arguments as well (default: "sendmail -t -i").
; http://php.net/sendmail-path
;sendmail_path =
; Force the addition of the specified parameters to be passed as extra parameters
; to the sendmail binary. These parameters will always replace the value of
; the 5th parameter to mail().
;mail.force_extra_parameters =
; Add X-PHP-Originating-Script: that will include uid of the script followed by the filename
mail.add_x_header = Off
; The path to a log file that will log all mail() calls. Log entries include
; the full path of the script, line number, To address and headers.
;mail.log =
; Log mail to syslog (Event Log on Windows).
;mail.log = syslog
然后让SMTP4DEV在同一端口上侦听。每次加载网页时，都会将新的会话日志添加到SMTP4DEV，但实际上并不会在电子邮件框中显示电子邮件。这是来自SMTP4DEV的会话日志：
220 localhost smtp4dev ready
QUIT
221 See you later aligator
有人知道这是什么问题吗，或者我如何查看一些日志以查找导致此问题的错误？