There is external software called "Fault Management" (aka "FM") that can send an email or SMS - based on an "event". Fault Management is a wonderful network management software package that has been engineered to connect to the 4K (and more recently the 8K/OSV). Fault Management receives the alarms, faults, and errors from the 4K, and allows the administrator to configure an action/response - such as SMS or email. For example, if the hard disk has failed, Fault Management can send an email to the technician. If IPDA has lost connectivity, a SMS can be sent to the network folks. Fault Management can manage all of the customer's network - not just the Telephony objects (4K and OSV). A free copy of Fault Management is provided with HiPath 4000 V6 and OpenScape 4000 V7. For all previous versions (V2-V5) there is a menu object on Assistant known as "Fault Management", but the FM "tool" that I am referring to is not provided. For all previous versions V2-V5, the Fault Management tool is a separate software package that can be installed on the HiPath 4000 Manager server, or a Linux server, or Windows server. It cannot be installed directly on the V2-V5 4K itself.
Other than FM, I know of no other way to generate an email based on an "event".