Mail Handler Split Regex behaviour with special characters (e.g. german umlauts)

Description

Hello META-INF team,

we recently setup the regular expression filter used in the JETI mail handler to strip off the old email's contents.
While testing this new regular expression we encounter the behaviour that the German umlauts (ö ä ü ß) were not parsed correctly.

At first we thought that this had to do with the specific regEx we were using but this can be reproduced with the example regular expression given in the mail handler configuration page:

With this regex set up as the split regex i sent two emails: the first did not include the matching "Original Message" string and the second did, leading to the result depicted in the attached images.

As can be seen in the screenshot, the first mail correctly displayed the umlauts and the remaining part of the mail, while the second mail correctly stripped off the unwanted content but lead to an incorrect display of the umlauts.

öäüß turns into öäüß

I was wondering if you had any insight on why this might occur and if it might be a configurational issue on our side or unexpected behaviour within the JETI code responsible for parsing the regex.

Thank you for taking the time to look into this, if any additional information is required I'd be happy to provide it.

Regards,
Fabian Kerkhoff

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Assignee

Tibor Hegyi

Reporter

Fabian Kerkhoff

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