Fixed the unit test for Validate/StringLength

library/Zend/Validate/StringLength.php

@@ -203,7 +203,11 @@ class Zend_Validate_StringLength extends Zend_Validate_Abstract
                         ? iconv_get_encoding('internal_encoding')
                         : ini_get('default_charset');
             if (PHP_VERSION_ID < 50600) {
-                $result = iconv_set_encoding('internal_encoding', $encoding);
+                if ($encoding) {
+                    $result = iconv_set_encoding('internal_encoding', $encoding);
+                } else {
+                    $result = false;
+                }
             } else {
                 ini_set('default_charset', $encoding);
                 $result = ini_get('default_charset');
@@ -219,7 +223,6 @@ class Zend_Validate_StringLength extends Zend_Validate_Abstract
                 ini_set('default_charset', $orig);
             }
         }
-
         $this->_encoding = $encoding;
         return $this;
     }