for E-Mail notification one can choose "Attach Build Log" at the extended options, when a Trigger (e.g. "failure") is added.
The option is not correctly stored in the config.xml for the job. The XML-Tag <attachBuildLog> always says "false". On editing this manually, the value is correctly displayed in the job-page. But every time I save the configuration the value is resetted.
relevant Config-page for job see attatched screenshot.