Garbled characters in log.log

I found a bug. When using the server code logging mechanism to print messages in non-English (in my case, Japanese UTF8 characters) I found all the non-English characters turn to ?? (question marks) in the log.log file after deploying my timer to production.

Hi, Simon.

Thank you for pointing out the bug.
We will fix this problem in next release.
Regards,
Kate.

Hi, Simon.
This issue is already resolved.

Regards,
Kate.