Description:
------------
When executing an external program via the expect:// wrapper everything works as expected except for the "shutdown". The program becomes a zombie and stays in the processlist until Apache is restarted. This does NOT occur when executing the PHP script via command line.

Same happens when executing screen or just something as simple as "echo", leaving the original shell, the program was executed in, as the zombie process.

This might be an PHP or Apache bug but I don't think so, as the problem doesn't occur when using for instance popen().

** PHP version: 5.0.5
'./configure' \
'--prefix=/usr/local' \
'--with-apxs2=/usr/bin/apxs2' \
'--with-config-file-path=/etc' \
'--with-mysql=/usr' \
'--enable-mbstring' \
'--with-gd' \
'--with-zlib' \
'--with-mysqli' \
'--with-gettext' \
'--with-mcrypt' \
'--with-imap' \
'--with-openssl' \
'--with-kerberos' \
'--with-imap-ssl' \
'--enable-ftp' \
'--with-freetype' \
'--with-freetype-dir=/usr/include/freetype2' \
'--with-jpeg' \
'--enable-sockets' \
'--enable-memory-limit' \
'--enable-pcntl' \
'--enable-pty' \
'--enable-shmop' \
'--enable-sysvsem' \
'--enable-sysvshm' \
'--enable-sigchild'
libexpect version: 5.43
Apache version: 2.0.54

Same happens when executing screen 

Reproduce code:
---------------
<?php

$shell = fopen('expect://bash', 'r+');
sleep(5);
fwrite($shell, "exit\n");
sleep(5);
fclose($shell);

// following seems to close the shell (fclose() fails afterwards) but the shell becomes a zombie nevertheless
$shell = fopen('expect://echo', 'r+');
sleep(5);
fwrite($shell, "exit\n");
sleep(5);
fclose($shell);

?>

Expected result:
----------------
A bash process starts and just to get terminated again.

Actual result:
--------------
% ps aux | grep defunct
www-data 21449  0.0  0.0      0     0 ?        Zs   23:53   0:00 [bash] <defunct>