Hello 'Mr I would cache mailbox, if I had the time', > An mbox cache could be done. This isn't really accurate. so please enlighten me and tell me what you would use as unique identifier for eMails? The message id? And tell me how you would invalidate a cache entry on a edited message? Using a md5 sum over the whole message? I see absolut no way of doing a *efficient* way to do mailbox header caching, but maybe you have some ideas. Please share! Honestly, Thomas