added global cookie prefix to get_cookie() unless the cookie exists as-requested
diff --git a/system/helpers/cookie_helper.php b/system/helpers/cookie_helper.php
index d906882..77f86e4 100644
--- a/system/helpers/cookie_helper.php
+++ b/system/helpers/cookie_helper.php
@@ -107,8 +107,14 @@
 {
 	function get_cookie($index = '', $xss_clean = FALSE)
 	{
-		$CI =& get_instance();
-		return $CI->input->cookie($index, $xss_clean);
+		$prefix = '';
+		
+		if ( ! isset($_COOKIE[$index]) && config_item('cookie_prefix') != '')
+		{
+			$prefix = config_item('cookie_prefix');
+		}
+		
+		return $CI->input->cookie($prefix.$index, $xss_clean);
 	}
 }