Blank page after deploying your CakePHP web app ?

Today I had this problem after uploading a CakePHP web app to the production server.
I had a blank page, nothing in the logs, no error messages…
After scratching my head for a long time I finally discovered it was an issue with CakePHP cache mecanism.
Delete the cache files in /www/app/tmp/cache/persistent/class.paths.php