diff --git a/system/core/CodeIgniter.php b/system/core/CodeIgniter.php
index 8affde6..13826c3 100644
--- a/system/core/CodeIgniter.php
+++ b/system/core/CodeIgniter.php
@@ -188,7 +188,7 @@
 	if ($EXT->call_hook('cache_override') === FALSE
 		&& $OUT->_display_cache($CFG, $URI) === TRUE)
 	{
-		exit;
+		exit(0);
 	}
 
 /*
diff --git a/system/core/Common.php b/system/core/Common.php
index d494caf..d638720 100644
--- a/system/core/Common.php
+++ b/system/core/Common.php
@@ -1,3 +1,4 @@
+
 <?php
 /**
  * CodeIgniter
@@ -175,7 +176,8 @@
 			// Note: We use exit() rather then show_error() in order to avoid a
 			// self-referencing loop with the Exceptions class
 			set_status_header(503);
-			exit('Unable to locate the specified class: '.$class.'.php');
+			echo 'Unable to locate the specified class: '.$class.'.php';
+			exit(2);
 		}
 
 		// Keep track of what we just loaded
@@ -248,14 +250,16 @@
 		elseif ( ! $found)
 		{
 			set_status_header(503);
-			exit('The configuration file does not exist.');
+			echo 'The configuration file does not exist.';
+			exit(1);
 		}
 
 		// Does the $config array exist in the file?
 		if ( ! isset($config) OR ! is_array($config))
 		{
 			set_status_header(503);
-			exit('Your config file does not appear to be formatted correctly.');
+			echo 'Your config file does not appear to be formatted correctly.';
+			exit(1);
 		}
 
 		// Are any values being dynamically replaced?
@@ -367,9 +371,20 @@
 	 */
 	function show_error($message, $status_code = 500, $heading = 'An Error Was Encountered')
 	{
+		$status_code = abs($status_code);
+		if ($status_code < 100)
+		{
+			$exit_status = $status_code + 28;
+			$status_code = 500;
+		}
+		else
+		{
+			$exit_status = 27;
+		}
+		
 		$_error =& load_class('Exceptions', 'core');
 		echo $_error->show_error($heading, $message, 'error_general', $status_code);
-		exit;
+		exit($exit_status);
 	}
 }
 
@@ -392,7 +407,7 @@
 	{
 		$_error =& load_class('Exceptions', 'core');
 		$_error->show_404($page, $log_error);
-		exit;
+		exit(4);
 	}
 }
 
@@ -514,11 +529,11 @@
 
 		if (strpos(php_sapi_name(), 'cgi') === 0)
 		{
-			header('Status: '.$code.' '.$text, TRUE);
+			if (!headers_sent()) header('Status: '.$code.' '.$text, TRUE);
 		}
 		else
 		{
-			header(($server_protocol ? $server_protocol : 'HTTP/1.1').' '.$code.' '.$text, TRUE, $code);
+			if (!headers_sent()) header(($server_protocol ? $server_protocol : 'HTTP/1.1').' '.$code.' '.$text, TRUE, $code);
 		}
 	}
 }
diff --git a/system/core/Exceptions.php b/system/core/Exceptions.php
index e6023e7..f799d60 100644
--- a/system/core/Exceptions.php
+++ b/system/core/Exceptions.php
@@ -117,7 +117,7 @@
 		}
 
 		echo $this->show_error($heading, $message, 'error_404', 404);
-		exit;
+		exit(4);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/core/Input.php b/system/core/Input.php
index 82e22dd..8f37e44 100644
--- a/system/core/Input.php
+++ b/system/core/Input.php
@@ -745,7 +745,8 @@
 		if ( ! preg_match('/^[a-z0-9:_\/|-]+$/i', $str))
 		{
 			set_status_header(503);
-			exit('Disallowed Key Characters.');
+			echo 'Disallowed Key Characters.';
+			exit(6);
 		}
 
 		// Clean UTF-8 if supported
diff --git a/system/core/Output.php b/system/core/Output.php
index a208414..7898d19 100644
--- a/system/core/Output.php
+++ b/system/core/Output.php
@@ -696,7 +696,7 @@
 		if (isset($_SERVER['HTTP_IF_MODIFIED_SINCE']) && $last_modified <= strtotime($_SERVER['HTTP_IF_MODIFIED_SINCE']))
 		{
 			$this->set_status_header(304);
-			exit;
+			exit(0);
 		}
 		else
 		{
diff --git a/system/database/DB_driver.php b/system/database/DB_driver.php
index 35ac8e8..cb2ef4a 100644
--- a/system/database/DB_driver.php
+++ b/system/database/DB_driver.php
@@ -1658,7 +1658,7 @@
 
 		$error =& load_class('Exceptions', 'core');
 		echo $error->show_error($heading, $message, 'error_db');
-		exit;
+		exit(5);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/helpers/download_helper.php b/system/helpers/download_helper.php
index 7294d50..d7691cb 100644
--- a/system/helpers/download_helper.php
+++ b/system/helpers/download_helper.php
@@ -141,7 +141,8 @@
 		// If we have raw data - just dump it
 		if ($data !== NULL)
 		{
-			exit($data);
+			echo $data;
+			exit(0);
 		}
 
 		// Flush 1MB chunks of data
@@ -151,7 +152,7 @@
 		}
 
 		fclose($fp);
-		exit;
+		exit(0);
 	}
 }
 
diff --git a/system/helpers/url_helper.php b/system/helpers/url_helper.php
index a6536cf..9a01535 100644
--- a/system/helpers/url_helper.php
+++ b/system/helpers/url_helper.php
@@ -549,7 +549,7 @@
 				header('Location: '.$uri, TRUE, $code);
 				break;
 		}
-		exit;
+		exit(0);
 	}
 }
 
diff --git a/system/libraries/Driver.php b/system/libraries/Driver.php
index 4b35dce..bb73189 100644
--- a/system/libraries/Driver.php
+++ b/system/libraries/Driver.php
@@ -291,7 +291,7 @@
 
 		$trace = debug_backtrace();
 		_exception_handler(E_ERROR, "No such method '{$method}'", $trace[1]['file'], $trace[1]['line']);
-		exit;
+		exit(3);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Trackback.php b/system/libraries/Trackback.php
index ecc7129..cc93b2e 100644
--- a/system/libraries/Trackback.php
+++ b/system/libraries/Trackback.php
@@ -212,7 +212,7 @@
 	public function send_error($message = 'Incomplete Information')
 	{
 		echo '<?xml version="1.0" encoding="utf-8"?'.">\n<response>\n<error>1</error>\n<message>".$message."</message>\n</response>";
-		exit;
+		exit(0);
 	}
 
 	// --------------------------------------------------------------------
@@ -228,7 +228,7 @@
 	public function send_success()
 	{
 		echo '<?xml version="1.0" encoding="utf-8"?'.">\n<response>\n<error>0</error>\n</response>";
-		exit;
+		exit(0);
 	}
 
 	// --------------------------------------------------------------------
diff --git a/system/libraries/Xmlrpcs.php b/system/libraries/Xmlrpcs.php
index d4524d2..465a196 100644
--- a/system/libraries/Xmlrpcs.php
+++ b/system/libraries/Xmlrpcs.php
@@ -170,7 +170,8 @@
 
 		header('Content-Type: text/xml');
 		header('Content-Length: '.strlen($payload));
-		exit($payload);
+		echo $payload;
+		exit(0);
 	}
 
 	// --------------------------------------------------------------------