diff --git a/install_postfix_base.sh b/install_postfix_base.sh
index ea5862b..f8f4a02 100755
--- a/install_postfix_base.sh
+++ b/install_postfix_base.sh
@@ -1103,11 +1103,20 @@ echo_ok
 echononl "   Configure SASL authentification"
 if $SASL_AUTH ; then
 
+   _sasl_pw_file="/etc/postfix/sasl_passwd"
+   if [[ -f "${_sasl_pw_file}" ]] && $(grep -q -E "^\[${RELAY_HOST}\]" ${_sasl_pw_file} 2> /dev/null); then
+      sed -i "/^\[${RELAY_HOST}/d" ${_sasl_pw_file}
+      if [[ "$?" != "0" ]]; then
+         error "Setting \"/etc/postfix/sasl_passwd\" failed! "
+         _failed=true
+      fi
+   fi
+
    _failed=false
    if [[ ${RELAY_PORT} -ne 25 ]] ; then
-      echo "[$RELAY_HOST]:${RELAY_PORT} ${SASL_USER}@${RELAY_HOST}:$SASL_PASS" > /etc/postfix/sasl_passwd
+      echo "[$RELAY_HOST]:${RELAY_PORT} ${SASL_USER}@${RELAY_HOST}:$SASL_PASS" >> /etc/postfix/sasl_passwd
    else
-      echo "[$RELAY_HOST] ${SASL_USER}@${RELAY_HOST}:$SASL_PASS" > /etc/postfix/sasl_passwd
+      echo "[$RELAY_HOST] ${SASL_USER}@${RELAY_HOST}:$SASL_PASS" >> /etc/postfix/sasl_passwd
    fi
    if [[ "$?" != "0" ]]; then
       error "Setting \"/etc/postfix/sasl_passwd\" failed! "