Update README to describe SMTP_CA_FILE

1 files changed, 4 insertions, 0 deletions

diff --git a/README.md b/README.md
index 65bdd2a..0898929 100644
--- a/README.md
+++ b/README.md
@@ -25,6 +25,10 @@ per-user).
 
 	define('SMTP_SKIP_CERT_CHECKS', false);
 	// Accept all SSL certificates, use with caution.
+
+	define('SMTP_CA_FILE', '/path/to/ca.crt');
+	// Use a custom CA certificate for SSL/TLS secure connections.
+	// Only used if SMTP_SKIP_CERT_CHECKS is false.
 ```
 
 At least SMTP_SERVER needs to set for plugin to work.