// use gzip compression if supported if (function_exists('ob_gzhandler') && ini_get('zlib.output_compression')) ob_start('ob_gzhandler');

After the change, things are getting better:

without compression "GET /?_task=mail&_action=show&_uid=150&_mbox=INBOX HTTP/1.1" 200 1754763

with compression "GET /?_task=mail&_action=show&_uid=150&_mbox=INBOX HTTP/1.1" 200 32523

Sorry for the noise...

Mirko

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