diff --git a/install/dist/lib/debian60.lib.php b/install/dist/lib/debian60.lib.php
index 42da878c3de2216bb9b6bf363a3c6e9874ff7191..49327239d746461e7b7c9e1ec2f9beeba0e6abb2 100644
--- a/install/dist/lib/debian60.lib.php
+++ b/install/dist/lib/debian60.lib.php
@@ -111,6 +111,7 @@ class installer extends installer_base {
 		$content = str_replace('{mysql_server_ispconfig_password}', $conf['mysql']['ispconfig_password'], $content);
 		$content = str_replace('{mysql_server_database}', $conf['mysql']['database'], $content);
 		$content = str_replace('{mysql_server_host}', $conf['mysql']['host'], $content);
+		$content = str_replace('{server_id}', $conf['server_id'], $content);
 		wf($config_dir.'/'.$configfile, $content);
 
 		chmod($config_dir.'/'.$configfile, 0600);
diff --git a/install/dist/lib/fedora.lib.php b/install/dist/lib/fedora.lib.php
index d3efe6022f26a63271a774e8f9cf6d3ddbe1221d..7a08f93f13d90716a9f5c3f661dca4d2732d8f2a 100644
--- a/install/dist/lib/fedora.lib.php
+++ b/install/dist/lib/fedora.lib.php
@@ -450,6 +450,7 @@ class installer_dist extends installer_base {
 		$content = str_replace('{mysql_server_ispconfig_password}', $conf['mysql']['ispconfig_password'], $content);
 		$content = str_replace('{mysql_server_database}', $conf['mysql']['database'], $content);
 		$content = str_replace('{mysql_server_host}', $conf['mysql']['host'], $content);
+		$content = str_replace('{server_id}', $conf['server_id'], $content);
 		wf("$config_dir/$configfile", $content);
 
 		exec("chmod 600 $config_dir/$configfile");
diff --git a/install/dist/lib/opensuse.lib.php b/install/dist/lib/opensuse.lib.php
index caef5409a8963ed3e5d419888ee1f70c1eb522d9..f990e919601bc4813f1a149862782d2c700cedb4 100644
--- a/install/dist/lib/opensuse.lib.php
+++ b/install/dist/lib/opensuse.lib.php
@@ -499,6 +499,7 @@ class installer_dist extends installer_base {
 		$content = str_replace('{mysql_server_ispconfig_password}', $conf['mysql']['ispconfig_password'], $content);
 		$content = str_replace('{mysql_server_database}', $conf['mysql']['database'], $content);
 		$content = str_replace('{mysql_server_host}', $conf['mysql']['host'], $content);
+		$content = str_replace('{server_id}', $conf['server_id'], $content);
 		wf("$config_dir/$configfile", $content);
 
 		exec("chmod 600 $config_dir/$configfile");
diff --git a/install/lib/installer_base.lib.php b/install/lib/installer_base.lib.php
index 2cd48a0797c042934d52de1f7b85bfc211f7a2b6..548cf9382a15686e5c501302c0cb4d9e92f97b95 100644
--- a/install/lib/installer_base.lib.php
+++ b/install/lib/installer_base.lib.php
@@ -1015,6 +1015,7 @@ class installer_base {
 		$content = str_replace('{mysql_server_ispconfig_password}', $conf['mysql']['ispconfig_password'], $content);
 		$content = str_replace('{mysql_server_database}', $conf['mysql']['database'], $content);
 		$content = str_replace('{mysql_server_host}', $conf['mysql']['host'], $content);
+		$content = str_replace('{server_id}', $conf['server_id'], $content);
 		wf($config_dir.'/'.$configfile, $content);
 
 		chmod($config_dir.'/'.$configfile, 0600);
diff --git a/install/tpl/debian6_dovecot-sql.conf.master b/install/tpl/debian6_dovecot-sql.conf.master
index 86eb4df6fe5a6f5d804a6beb2cdab63a7afd7404..61f86c4cfa6f14dbb6dfa87069bb704337a071c1 100644
--- a/install/tpl/debian6_dovecot-sql.conf.master
+++ b/install/tpl/debian6_dovecot-sql.conf.master
@@ -13,8 +13,8 @@ driver = mysql
 connect = host={mysql_server_host} dbname={mysql_server_database} user={mysql_server_ispconfig_user} password={mysql_server_ispconfig_password}
 default_pass_scheme = CRYPT
 
-password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n'
-user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND `disable%Ls` = 'n'
+password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n' AND server_id = '{server_id}'
+user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND `disable%Ls` = 'n' AND server_id = '{server_id}'
 
 # The iterate_query is required for the doveadm command only and works only on dovecot 2 servers.
 # Do not enable it on Dovecot 1.x servers
diff --git a/install/tpl/debian_dovecot-sql.conf.master b/install/tpl/debian_dovecot-sql.conf.master
index 9c55df358f90f71291c3fdfa13d3d99c976d98af..a4d5bbd95d815a206dc3dbec3c29ec8cb7e22254 100644
--- a/install/tpl/debian_dovecot-sql.conf.master
+++ b/install/tpl/debian_dovecot-sql.conf.master
@@ -120,8 +120,8 @@ driver = mysql
 connect = host={mysql_server_host} dbname={mysql_server_database} user={mysql_server_ispconfig_user} password={mysql_server_ispconfig_password}
 default_pass_scheme = CRYPT
 
-password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n'
-user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n'
+password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n' AND server_id = '{server_id}'
+user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n' AND server_id = '{server_id}'
 
 # The iterate_query is required for the doveadm command only and works only on dovecot 2 servers.
 # Do not enable it on Dovecot 1.x servers
diff --git a/install/tpl/fedora_dovecot-sql.conf.master b/install/tpl/fedora_dovecot-sql.conf.master
index faf3be286c7283700e1a45e1e802acb0b77acbdf..769e0a4a0d117ac32327afa0b8069737ca27592f 100644
--- a/install/tpl/fedora_dovecot-sql.conf.master
+++ b/install/tpl/fedora_dovecot-sql.conf.master
@@ -133,8 +133,8 @@ driver = mysql
 connect = host={mysql_server_host} dbname={mysql_server_database} user={mysql_server_ispconfig_user} password={mysql_server_ispconfig_password}
 default_pass_scheme = CRYPT
 
-password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n'
-user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND `disable%Ls` = 'n'
+password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n' AND server_id = '{server_id}'
+user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND `disable%Ls` = 'n' AND server_id = '{server_id}'
 
 # The iterate_query is required for the doveadm command only and works only on dovecot 2 servers.
 # Do not enable it on Dovecot 1.x servers
diff --git a/install/tpl/opensuse_dovecot-sql.conf.master b/install/tpl/opensuse_dovecot-sql.conf.master
index e33603a1c20ac7332d9608e172286bfc83fb0ef0..57515afe872099e2652258d58730f8a388fb65fd 100644
--- a/install/tpl/opensuse_dovecot-sql.conf.master
+++ b/install/tpl/opensuse_dovecot-sql.conf.master
@@ -133,8 +133,8 @@ driver = mysql
 connect = host={mysql_server_host} dbname={mysql_server_database} user={mysql_server_ispconfig_user} password={mysql_server_ispconfig_password}
 default_pass_scheme = CRYPT
 
-password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n'
-user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND `disable%Ls` = 'n'
+password_query = SELECT password FROM mail_user WHERE (login = '%u' OR email = '%u') AND disable%Ls = 'n' AND server_id = '{server_id}'
+user_query = SELECT email as user, maildir as home, CONCAT('maildir:', maildir, '/Maildir') as mail, uid, gid, CONCAT('*:storage=', quota, 'B') AS quota_rule, CONCAT(maildir, '/.sieve') as sieve FROM mail_user WHERE (login = '%u' OR email = '%u') AND `disable%Ls` = 'n' AND server_id = '{server_id}'
 
 # The iterate_query is required for the doveadm command only and works only on dovecot 2 servers.
 # Do not enable it on Dovecot 1.x servers