Aha! There's the issue: 
% diff foo.pl bar.pl 
7c7
< $msg->build(subject => 'a message subject')->data('Data2');
---
> $msg->build(subject => 'a message subject');

foo.pl -> 0
bar.pl -> 1

[download]
Why is the ->data() required?

In reply to Re^6: Error in MIME::Lite? by littlelion
in thread Error in MIME::Lite? by littlelion

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