initialize map to prevent runtime panic
diff --git a/servers.go b/servers.go
index dacf9f6..05157e2 100644
--- a/servers.go
+++ b/servers.go
@@ -317,7 +317,7 @@
 
 // See the CloudServersProvider interface for details.
 func (gsp *genericServersProvider) ListAddressesByNetwork(id, networkLabel string) (NetworkAddress, error){
-	var pas NetworkAddress
+	pas := make(NetworkAddress)
 	var statusCode int
 
 	err := gsp.context.WithReauth(gsp.access, func() error {