diff --git a/docs/prerequisite-system.md b/docs/prerequisite-system.md
index c70415166..ecf6dbf96 100644
--- a/docs/prerequisite-system.md
+++ b/docs/prerequisite-system.md
@@ -59,17 +59,19 @@ If this command returns any results please remove or stop the application runnin
 
 If you have a firewall in front of mailcow, please make sure that these ports are open for incoming connections:
 
-| Service             | Protocol | Port   | Container       | Variable                         |
-| --------------------|:--------:|:-------|:----------------|----------------------------------|
-| Postfix SMTP        | TCP      | 25     | postfix-mailcow | `${SMTP_PORT}`                   |
-| Postfix SMTPS       | TCP      | 465    | postfix-mailcow | `${SMTPS_PORT}`                  |
-| Postfix Submission  | TCP      | 587    | postfix-mailcow | `${SUBMISSION_PORT}`             |
-| Dovecot IMAP        | TCP      | 143    | dovecot-mailcow | `${IMAP_PORT}`                   |
-| Dovecot IMAPS       | TCP      | 993    | dovecot-mailcow | `${IMAPS_PORT}`                  |
-| Dovecot POP3        | TCP      | 110    | dovecot-mailcow | `${POP_PORT}`                    |
-| Dovecot POP3S       | TCP      | 995    | dovecot-mailcow | `${POPS_PORT}`                   |
-| Dovecot ManageSieve | TCP      | 4190   | dovecot-mailcow | `${SIEVE_PORT}`                  |
-| HTTP(S)             | TCP      | 80/443 | nginx-mailcow   | `${HTTP_PORT}` / `${HTTPS_PORT}` |
+| Service             | Protocol | Port   | Container         | Variable                         |
+| --------------------|:--------:|:-------|:------------------|----------------------------------|
+| Postfix SMTP        | TCP      | 25     | postfix-mailcow   | `${SMTP_PORT}`                   |
+| Postfix SMTPS       | TCP      | 465    | postfix-mailcow   | `${SMTPS_PORT}`                  |
+| Postfix Submission  | TCP      | 587    | postfix-mailcow   | `${SUBMISSION_PORT}`             |
+| Dovecot IMAP        | TCP      | 143    | dovecot-mailcow   | `${IMAP_PORT}`                   |
+| Dovecot IMAPS       | TCP      | 993    | dovecot-mailcow   | `${IMAPS_PORT}`                  |
+| Dovecot POP3        | TCP      | 110    | dovecot-mailcow   | `${POP_PORT}`                    |
+| Dovecot POP3S       | TCP      | 995    | dovecot-mailcow   | `${POPS_PORT}`                   |
+| Dovecot ManageSieve | TCP      | 4190   | dovecot-mailcow   | `${SIEVE_PORT}`                  |
+| HTTP(S)             | TCP      | 80/443 | nginx-mailcow     | `${HTTP_PORT}` / `${HTTPS_PORT}` |
+| XMPP (c2s)          | TCP      | 5222   | ejabberd-mailcow  | `${XMPP_C2S_PORT}`               |
+| XMPP (s2s)          | TCP      | 5269   | ejabberd-mailcow  | `${XMPP_C2S_PORT}`               |
 
 To bind a service to an IP address, you can prepend the IP like this: `SMTP_PORT=1.2.3.4:25`