Blank Page Encountered When Moved Wp-content Directory Outside - wordpress

Question

I'm trying to install Wordpress with clean subversion repositories, as in http://codex.wordpress.org/Installing_WordPress_With_Clean_Subversion_Repositories. I have followed every step accordingly until the second last step, where it says 'You should now be able to view the site via the root URL (http://example.com)', and indeed I can see my website on, say, http://example.com.
Once I go to the final step of changing the wp-config.php though, http://example.com draws a blank page. I am quite sure the wp-config.php is the problem, i.e. Wordpress doesn't know that it should retrieve my wp-content contents from outside the core Wordpress directory. My directory structure is as such:
.htaccess
core/
custom/
wp-config.php
, where core/ holds the files checked out with Subversion, custom/ holds my themes/ and plugins/ directory, and wp-config.php contains the below lines:
define('WP_CONTENT_DIR', dirname(__FILE__) . '/custom');
define('WP_CONTENT_URL', 'http://example.com/custom');
I have tried other variations, like:
define('WP_CONTENT_DIR', $_SERVER['DOCUMENT_ROOT'] . '/custom');
define('WP_CONTENT_URL', 'http://example.com/custom');
I have also tried hardcoding the local path, like:
define('WP_CONTENT_DIR', '/home/MYUSERNAME/example.com/custom');
define('WP_CONTENT_URL', 'http://example.com/custom');
, but none of the above works. Then I renamed the custom/ folder to wp-content/, but again nothing. I even went into Dreamhost to prevent redirecting http://example.com to http://www.example.com and vice versa, but again to no avail. I don't believe core/ is the problem, because I can access the Dashboard via http://example.com/core/wp-login.php, and the Dashboard says it can't detect my themes, which confirms my suspicion that WP doesn't know to retrieve the files from the custom/ folder.
By now, I have run out of ideas as to where could the problem be. Can anyone experienced in this area please give me some advice? Thanks a million.

Answer 1

Ensure that your statements come BEFORE the call for wp-settings.php, which is usually around line 90. Wp-settings (or more accurately default-constants.php) checks if the paths and URLs have already been defined, so you want to make sure you define them beforehand.
If that isn't the issue then check if $_SERVER['DOCUMENT_ROOT'] is returning the values you expect; you might have issues if working in a sub-directory.