from the rfc:
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encapsulation := delimiter transport-padding
                      CRLF body-part
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and also
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"Composers MUST NOT generate non-zero length transport
padding, but receivers MUST be able to handle padding
added by message transports."
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second part have a start boundary ending with spaces
and also have a boundary not at the beginning
 --boundary
... that should be ignored

also a boundary with more data (a tab) shoud be ignored
 --boundary	
 
end of part