Jetpack post by email truncating at lines with multiple hyphens

Post by email is resulting in truncated posts at the first instance of multiple hyphens. This is particularly problematic if one uses Markdown formatting.

Not all the time, but in predictable cases.

For instance, the following email message results in a post truncated after line 1:

A header
--------

Then some more

Similarly, the following gets truncated at the first "row" divider of hyphens:

A markdown table

| Fruit       | Color           | Note        | 
| ----------- | --------------- | ----------- |  
| Bananas     | Yellow          | Monkeys!    | 

Note: not ALL instances of multiple hyphens are problematic, the following email post works fine:

Some stuff followed by a hard rule

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Bam.