PostgreSQL 11 sends shared secret to RADIUS server in all low case

PostgreSQL 11 sends shared secret to RADIUS server in all low case for user authentication. Does anyone know why? How to correct it?

Best regards,

Min Wang
Global Data Services
New York Stock Exchange
An Intercontinental Exchange Company (NYSE: ICE)
11 Wall St. | New York, NY 10005
Tel: +1 212.656.2441 | Mob: +1 201.936.9888
Min(dot)Wang(at)theice(dot)com<mailto:Min(dot)Wang(at)theice(dot)com>
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