When a custom pager subject is used, for both MIME/non-MIME patch, there is only one newline instead of two: https://github.com/asterisk/asterisk/blob/master/apps/app_voicemail.c#L6028
This causes the message to be ill-formatted since there is no blank line between the headers and the body.
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9/28/2024 3:28 PM — InterLinked
Resolved by https://github.com/asterisk/asterisk/pull/903