v5.8.0 had some issues with its handling of UTF-8 that were fixed in 5.8.1. I would highly recommend upgrading, if possible. If not, here are some pointers to changes:

Also in the delta is this information about updates to the Encode module:

Significant updates on the encoding pragma functionality (tr/// and the DATA filehandle, formats).
If a filehandle has been marked as to have an encoding, unmappable characters are detected already during input, not later (when the corrupted data is being used).
...

Hope this helps

In reply to Re: When is the utf8-flag turned on? by benizi
in thread When is the utf8-flag turned on? by uwevoelker

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