By default the emailgtw probe character length is set to ?100" for emails' Subject line, however you can increase the character length in the subject by adding the ?subject_length" setup key / parameter in the emailgtw probe via the Raw Configure window.
1. The value should not exceed 998 or else you might not receive mail in outlook as it rejects mails with Subject greater than 998 (as per RFC)
2. The value should always be an integer.
3. To do this, highlight the probe and hold down the SHIFT key and rt-click to enter Raw Configure mode.
4. Under the setup section enter the new key and value.