diff --git a/functions b/functions
index 8cb703c567..80d1f619da 100644
--- a/functions
+++ b/functions
@@ -553,6 +553,56 @@ $option = $value
     fi
 }
 
+# Get a multiple line option from an INI file
+# iniget_multiline config-file section option
+function iniget_multiline() {
+    local file=$1
+    local section=$2
+    local option=$3
+    local values
+    values=$(sed -ne "/^\[$section\]/,/^\[.*\]/ { s/^$option[ \t]*=[ \t]*//gp; }" "$file")
+    echo ${values}
+}
+
+# Set a multiple line option in an INI file
+# iniset_multiline config-file section option value1 value2 valu3 ...
+function iniset_multiline() {
+    local file=$1
+    local section=$2
+    local option=$3
+    shift 3
+    local values
+    for v in $@; do
+        # The later sed command inserts each new value in the line next to
+        # the section identifier, which causes the values to be inserted in
+        # the reverse order. Do a reverse here to keep the original order.
+        values="$v ${values}"
+    done
+    if ! grep -q "^\[$section\]" "$file"; then
+        # Add section at the end
+        echo -e "\n[$section]" >>"$file"
+    else
+        # Remove old values
+        sed -i -e "/^\[$section\]/,/^\[.*\]/ { /^$option[ \t]*=/ d; }" "$file"
+    fi
+    # Add new ones
+    for v in $values; do
+        sed -i -e "/^\[$section\]/ a\\
+$option = $v
+" "$file"
+    done
+}
+
+# Append a new option in an ini file without replacing the old value
+# iniadd config-file section option value1 value2 value3 ...
+function iniadd() {
+    local file=$1
+    local section=$2
+    local option=$3
+    shift 3
+    local values="$(iniget_multiline $file $section $option) $@"
+    iniset_multiline $file $section $option $values
+}
 
 # is_service_enabled() checks if the service(s) specified as arguments are
 # enabled by the user in ``ENABLED_SERVICES``.
diff --git a/lib/nova b/lib/nova
index 374979089d..89dc3f77ce 100644
--- a/lib/nova
+++ b/lib/nova
@@ -428,8 +428,7 @@ function create_nova_conf() {
     if is_service_enabled ceilometer; then
         iniset $NOVA_CONF DEFAULT instance_usage_audit "True"
         iniset $NOVA_CONF DEFAULT instance_usage_audit_period "hour"
-        iniset $NOVA_CONF DEFAULT notification_driver "nova.openstack.common.notifier.rpc_notifier"
-        iniset $NOVA_CONF DEFAULT notification_driver "ceilometer.compute.nova_notifier"
+        iniset_multiline $NOVA_CONF DEFAULT notification_driver "nova.openstack.common.notifier.rpc_notifier" "ceilometer.compute.nova_notifier"
     fi
 
 
diff --git a/tests/functions.sh b/tests/functions.sh
index 4fe644367d..27a6cfeec4 100755
--- a/tests/functions.sh
+++ b/tests/functions.sh
@@ -60,6 +60,10 @@ spaces  =  yes
 
 [ddd]
 empty =
+
+[eee]
+multi = foo1
+multi = foo2
 EOF
 
 # Test with spaces
@@ -193,6 +197,34 @@ else
     echo "inicomment failed: $VAL"
 fi
 
+# Test multiple line iniset/iniget
+iniset_multiline test.ini eee multi bar1 bar2
+
+VAL=$(iniget_multiline test.ini eee multi)
+if [[ "$VAL" == "bar1 bar2" ]]; then
+    echo "OK: iniset_multiline"
+else
+    echo "iniset_multiline failed: $VAL"
+fi
+
+# Test iniadd with exiting values
+iniadd test.ini eee multi bar3
+VAL=$(iniget_multiline test.ini eee multi)
+if [[ "$VAL" == "bar1 bar2 bar3" ]]; then
+    echo "OK: iniadd"
+else
+    echo "iniadd failed: $VAL"
+fi
+
+# Test iniadd with non-exiting values
+iniadd test.ini eee non-multi foobar1 foobar2
+VAL=$(iniget_multiline test.ini eee non-multi)
+if [[ "$VAL" == "foobar1 foobar2" ]]; then
+    echo "OK: iniadd with non-exiting value"
+else
+    echo "iniadd with non-exsting failed: $VAL"
+fi
+
 rm test.ini
 
 # Enabling/disabling services