Missing =back.
Part of PR 196

doc/ssl/SSL_CTX_set_msg_callback.pod

diff --git a/doc/ssl/SSL_CTX_set_msg_callback.pod b/doc/ssl/SSL_CTX_set_msg_callback.pod
index a423932..0015e6e 100644
--- a/doc/ssl/SSL_CTX_set_msg_callback.pod
+++ b/doc/ssl/SSL_CTX_set_msg_callback.pod
@@ -69,6 +69,8 @@
 The user-defined argument optionally defined by
 SSL_CTX_set_msg_callback_arg() or SSL_set_msg_callback_arg().
 
+=back
+
 =head1 NOTES
 
 Protocol messages are passed to the callback function after decryption