_isPathWriteable giving error: The given destination is not writable

[woranl]

Sometimes when multiple file transfers take place in parallel, an error may arise saying The given destination is not writable. It appears that in the _isPathWriteable function of Zend/File/Transfer/Adapter/Abstract.php, the $tempFile .= '/' . 'test.1'; is rather limiting. Multiple transfers may have tried to write text.1 at the same time, resulting in the error. Perhaps some randomness like $tempFile .= '/' . 'test.'.mt_rand(1, 1000); should be use instead to avoid the chance of collision.