==== Required information ====
- iRedMail version: 0.9.2
- Store mail accounts in which backend (LDAP/MySQL/PGSQL): MySQL
- Web server (Apache or Nginx): Apache
- Linux/BSD distribution name and version: Debian 8
- Related log if you're reporting an issue: /var/log/mail.log
====

After updating to 0.9.2 last night, I started getting this error in mail.log, which appears to be for Roundcube and php-pear-related:

Jun  4 15:38:37 mail roundcube: PHP Deprecated:  Non-static method PEAR::isError() should not be called statically, assuming $this from incompatible context in /opt/www/roundcubemail-1.1.1/vendor/pear/net_smtp/Net/SMTP.php on line 263
Jun  4 15:38:37 mail roundcube: PHP Deprecated:  Non-static method PEAR::isError() should not be called statically, assuming $this from incompatible context in /opt/www/roundcubemail-1.1.1/vendor/pear/net_smtp/Net/SMTP.php on line 1057
Jun  4 15:38:37 mail roundcube: PHP Deprecated:  Non-static method PEAR::isError() should not be called statically, assuming $this from incompatible context in /opt/www/roundcubemail-1.1.1/vendor/pear/net_smtp/Net/SMTP.php on line 1117

Any clue as to what is going on here, anyone? I only noticed this after after upgrading to 0.9.2.