SSL initialization error - Dovecot 2.4.1, Fedora 43 beta

I'm trying Dovecot 2.4.1 under Fedora 43 beta with all packages up to date. I've encountered several issues after attempting to update my configuration. The main problem is this: whenever a client attempts to connect, I get the following error

Error: Failed to initialize SSL connection: Couldn't initialize SSL server context: Can't load SSL certificate (ssl_server_cert_file setting): error:0A00018F:SSL routines::ee key too small:

I'm using a SECP384R1 key issued by letsencrypt.org, which should satisfy security checks. My Web searches have not identified a relevant bug report.

Have others encountered this issue? If it's distribution-specific, I can visit the relevant bug tracker.

Thank you for your consideration.