use non system ports

Dockerfile

@@ -22,10 +22,10 @@ USER davmail
 VOLUME ["/etc/davmail/davmail.p12"]
 
 EXPOSE     1080
-EXPOSE     993
-EXPOSE     636
-EXPOSE     995
-EXPOSE     587
+EXPOSE     1993
+EXPOSE     1636
+EXPOSE     1995
+EXPOSE     1587
 
 WORKDIR    /opt/davmail
 ENTRYPOINT ["/opt/davmail/entrypoint.sh"]

content/etc/davmail/davmail.properties.template

@@ -12,10 +12,10 @@ davmail.url=${DAVMAIL_URL}
 
 # Listener ports
 davmail.caldavPort=1080
-davmail.imapPort=993
-davmail.ldapPort=636
-davmail.popPort=995
-davmail.smtpPort=587
+davmail.imapPort=1993
+davmail.ldapPort=1636
+davmail.popPort=1995
+davmail.smtpPort=1587
 
 #############################################################
 # Network settings