I had a bunch of problems with this myself with plain text e-mails from Linux systems (just text files shoved out using /bin/mail). I did bunches of translation and tried every line ending I could to get what I wanted. I think I eventually stumbled across Line breaks are removed in posts made in plain text format in Outlook. I don't know if that will help (especially since you are using MIME e-mails), but it's worth a look.

In reply to Re^6: Losing eol character using MIME::Lite by Sinistral
in thread Losing eol character using MIME::Lite by cbeckley

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