Re : Strange behavior with regisrtationmail/Mac/French
Just ideas:
1) Did you try the option admin -> general -> default charset for sending email with the value iso-8859-1?
What is the mac mail agent?
2) did you try to clean the cache? admin -> system admin -> clean templates_c ?
If a mac user register and after a Windows user register, is the message receive by the windows user complete?
3) has the name of the user who registers characters with accent (I just fix a bug on the link)
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