diff --git a/sanity_check.php b/sanity_check.php
index 35d5c2a7f..d70445e02 100644
--- a/sanity_check.php
+++ b/sanity_check.php
@@ -11,6 +11,7 @@
 	}
 
 	require_once "config.php";
+	require_once "sanity_config.php";
 
 	if (CONFIG_VERSION != EXPECTED_CONFIG_VERSION) {
 		$err_msg = "config: your config file version is incorrect. See config.php-dist.\n";
@@ -22,6 +23,16 @@
 		$err_msg = "config: HTMLPurifier cache directory should be writable by anyone (chmod -R 777 $purifier_cache_dir)";
 	}
 
+	if (GENERATED_CONFIG_CHECK != EXPECTED_CONFIG_VERSION) {
+		$err_msg = "config: your sanity_config.php is outdated, please recreate it using ./utils/regen_config_checks.sh";
+	}
+
+	foreach ($requred_defines as $d) {
+		if (!defined($d)) {
+			$err_msg = "config: required constant $d is not defined. Please check config.php";
+		}
+	}
+
 	if (defined('RSS_BACKEND_TYPE')) {
 		print "<b>Fatal error</b>: RSS_BACKEND_TYPE is deprecated. Please remove this
 			option from config.php\n";
diff --git a/sanity_config.php b/sanity_config.php
new file mode 100644
index 000000000..6410c5407
--- /dev/null
+++ b/sanity_config.php
@@ -0,0 +1,3 @@
+<?php # This file has been generated at:  Tue Jan 11 12:10:54 MSK 2011
+define('GENERATED_CONFIG_CHECK', 21);
+$requred_defines = array( 'DB_TYPE', 'DB_HOST', 'DB_USER', 'DB_NAME', 'DB_PASS', 'DB_PORT', 'MAGPIE_FETCH_TIME_OUT', 'MAGPIE_CACHE_DIR', 'MAGPIE_CACHE_AGE', 'ICONS_DIR', 'ICONS_URL', 'SINGLE_USER_MODE', 'TMP_DIRECTORY', 'ENABLE_UPDATE_DAEMON', 'DAEMON_SLEEP_INTERVAL', 'DATABASE_BACKED_SESSIONS', 'SESSION_CHECK_ADDRESS', 'SESSION_COOKIE_LIFETIME', 'SESSION_EXPIRE_TIME', 'DAEMON_UPDATE_LOGIN_LIMIT', 'CHECK_FOR_NEW_VERSION', 'USE_CURL', 'DIGEST_ENABLE', 'DIGEST_EMAIL_LIMIT', 'DAEMON_SENDS_DIGESTS', 'ENABLE_TRANSLATIONS', 'MYSQL_CHARSET', 'DEFAULT_UPDATE_METHOD', 'SIMPLEPIE_CACHE_DIR', 'SIMPLEPIE_CACHE_IMAGES', 'COUNTERS_MAX_AGE', 'DIGEST_FROM_NAME', 'DIGEST_FROM_ADDRESS', 'DIGEST_SUBJECT', 'DIGEST_SMTP_HOST', 'DIGEST_SMTP_LOGIN', 'DIGEST_SMTP_PASSWORD', 'DAEMON_FEED_LIMIT', 'ALLOW_REMOTE_USER_AUTH', 'AUTO_LOGIN', 'LOCK_DIRECTORY', 'ENABLE_GZIP_OUTPUT', 'PHP_EXECUTABLE', 'ENABLE_REGISTRATION', 'REG_NOTIFY_ADDRESS', 'REG_MAX_USERS', 'FEEDBACK_URL', 'FORCE_ARTICLE_PURGE', 'SPHINX_ENABLED', 'SPHINX_INDEX', 'ENABLE_TWEET_BUTTON', 'CONSUMER_KEY', 'CONSUMER_SECRET', 'CONFIG_VERSION'); ?>
diff --git a/utils/regen_config_checks.sh b/utils/regen_config_checks.sh
new file mode 100755
index 000000000..78f2dbfba
--- /dev/null
+++ b/utils/regen_config_checks.sh
@@ -0,0 +1,17 @@
+#!/bin/sh
+
+DESTINATION="sanity_config.php"
+
+echo "<?php # This file has been generated at: " `date` > $DESTINATION
+
+echo -n "define('GENERATED_CONFIG_CHECK', " >> $DESTINATION
+grep CONFIG_VERSION config.php-dist | awk -F ' |)' '{ print $2 }' | xargs echo -n >> $DESTINATION
+echo ");" >> $DESTINATION
+
+echo -n "\$requred_defines = array( " >> $DESTINATION
+
+grep define\( config.php-dist | awk -F\' '{ print "*" $2 "*," }' | xargs echo -n | sed -e s/,$// -e s/*/\'/g >> $DESTINATION
+
+echo "); ?>" >> $DESTINATION
+
+