Signing & the "-" character

[Abhay S. Kushwaha]

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Whenever I sign an email message, any sentence starting with the dash
character "-" gets an additional "- " prepended. So a sentence that is

---- There are 4 - here

becomes

- ---- There are 4 - here

once the signing is done. This apparently also only happens in the
case when I sign 'inline' or sign the contents of the clipboard.

1. Why does this happen?
2. Is this intentional or a side effect of something?
3. Can this be avoided? If so, how?
4. What other characters are similarly prepended?

I am new and so I want to know. If these questions are answered
on a website(s), please let me know the URL(s).

BTW, I'm on Win32 if it makes any difference in this regard.

TIA

[abhay]

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