public function clearPaths($prefix = null)
    {
        if ((null !== $prefix) && is_string($prefix)) {
            $prefix = $this->_formatPrefix($prefix);
            if ($this->_useStaticRegistry) {
                if (isset(self::$_staticPrefixToPaths[$this->_useStaticRegistry][$prefix])) {
                    unset(self::$_staticPrefixToPaths[$this->_useStaticRegistry][$prefix]);
                    return true;
                }

                return false;
            }

            if (isset($this->_prefixToPaths[$prefix])) {
                unset($this->_prefixToPaths[$prefix]);
                return true;
            }

            return false;
        }

        if ($this->_useStaticRegistry) {
            self::$_staticPrefixToPaths[$this->_useStaticRegistry] = array();
        } else {
            $this->_prefixToPaths = array();
        }

        return true;
    }