Index: install.php
===================================================================
RCS file: /cvs/drupal/drupal/install.php,v
retrieving revision 1.237
diff -u -p -r1.237 install.php
--- install.php	17 Feb 2010 04:19:51 -0000	1.237
+++ install.php	22 Oct 2010 01:31:40 -0000
@@ -1,6 +1,12 @@
 <?php
 // $Id: install.php,v 1.237 2010/02/17 04:19:51 webchick Exp $
 
+// Exit early if running an incompatible PHP version to avoid fatal errors.
+if (version_compare(PHP_VERSION, '5.2.4') < 0) {
+  print 'Your PHP installation is too old. Drupal requires at least PHP 5.2.4. See the <a href="http://drupal.org/requirements">system requirements</a> page for more information.';
+  exit;
+}
+
 /**
  * @file
  * Initiates a browser-based installation of Drupal.