We should replace default config's string

Makefile

@@ -116,7 +116,7 @@ server: zabbix-server-service zabbix-server-config httpd-conf
 	sed -e 's|^DBUser=.*|# DBUser=|' -i /etc/zabbix_server.conf
 	sed -e 's|^Timeout=.*|Timeout=10|' -i /etc/zabbix_server.conf
 	sed -e 's|^# Include=/usr/local/etc/zabbix_server\.conf\.d/\*\.conf|Include=/etc/zabbix_server.conf.d/*.conf|' -i /etc/zabbix_server.conf
-	sed -e '/^# StartIPMIPollers=0/a StartIPMIPollers=1' -i /etc/zabbix_server.conf
+	sed -e 's|^# StartIPMIPollers=0|StartIPMIPollers=1|' -i /etc/zabbix_server.conf
 	cp -rv zabbix-5.0.1/ui/* /srv/www
 	cp zabbix.conf.php /srv/www/conf
 	rm /srv/www/conf/zabbix.conf.php.example