Description:
------------
I have a CLI PHP script that is run via cron.  Most of the time (about 75%) it runs without issue.  Sometimes, however, I get output similar to the following in my log file:

[01-Sep-2005 13:30:40] PHP Notice:  Undefined index:  HOME in /path/to/file.php on line xx
[01-Sep-2005 13:30:40] Array
(
    [PATH] => /bin:/sbin:/usr/bin:/usr/sbin:/usr/libexec:/System/Library/CoreServices
    [PWD] => /
    [SHLVL] => 3
    [_] => /usr/sbin/httpd
)

Note that PHP and only PHP writes into this log file.

Reproduce code:
---------------
$scriptdir = "$_ENV[HOME]/automation";
error_log(print_r($_ENV,true));



Expected result:
----------------
I expect to see the $_ENV array printed into the log file, with the name of the currently running php script in $_ENV['_'].  I also expect to see no error from the line that references $_ENV['HOME'].  

Here is a "normal" entry, generated by the exact same script:

[01-Sep-2005 13:46:01] Array
(
    [SHELL] => /bin/sh
    [USER] => wbd
    [SCRIPT_PATH] => /Users/wbd/automation
    [PATH] => /usr/bin:/bin
    [PWD] => /Users/wbd
    [SHLVL] => 1
    [HOME] => /Users/wbd
    [LOG_PATH] => /Users/wbd/automation/_logs
    [LOGNAME] => wbd
    [_] => /Users/wbd/automation/_shared/everyMinute.php
    [__CF_USER_TEXT_ENCODING] => 0x1F5:0:0
)

Actual result:
--------------
See log entry above.