Description:
------------
is_dir throws an error if:
- open_basedir is in effect
- called upon a file
- the path is terminated with a slash

CLI Tested on Windows:
php -d open_basedir=/ -r "var_dump(is_dir('C:/Windows/write.exe'));"
#bool(false)
php -d open_basedir=/ -r "var_dump(is_dir('C:/Windows/write.exe/'));"
#warning

CLI Not tested on Linux, should be like this:
php -d open_basedir=/ -r "var_dump(is_dir('/etc/fstab'));"

Apache2 module tested on Debian, see test script.

Test script:
---------------
<?php

echo PHP_VERSION . PHP_EOL;
ini_set('display_errors', true);
error_reporting(E_ALL);
var_dump(is_dir(__FILE__ . '/'));


Expected result:
----------------
5.2.9-0.dotdeb.1 bool(false)

Actual result:
--------------
5.3.5-0.dotdeb.0
Warning: is_dir() [function.is-dir]: open_basedir restriction in effect. File(/var/www/vhosts/blah/subdomains/bleah/httpdocs/phpinfo.php/) is not within the allowed path(s): (/var/www/vhosts/blah/subdomains/bleah/httpdocs:/tmp) in /var/www/vhosts/blah/subdomains/bleah/httpdocs/phpinfo.php on line 7
bool(false)