diff --git a/src/requests/zone.cr b/src/requests/zone.cr
index d06c775..e9c2c31 100644
--- a/src/requests/zone.cr
+++ b/src/requests/zone.cr
@@ -6,7 +6,7 @@ class DNSManager::Request
 	IPC::JSON.message NewDomain, 9 do
 		property domain : String
 
-		def initialize(@zone)
+		def initialize(@domain)
 		end
 
 		def handle(dnsmanagerd : DNSManager::Service, event : IPC::Event) : IPC::JSON
diff --git a/src/responses/error.cr b/src/responses/error.cr
index 9d51538..05d4ea8 100644
--- a/src/responses/error.cr
+++ b/src/responses/error.cr
@@ -12,4 +12,10 @@ class DNSManager::Response
 		end
 	end
 	DNSManager.responses << ErrorInvalidToken
+
+	IPC::JSON.message DomainAlreadyExists, 3 do
+		def initialize()
+		end
+	end
+	DNSManager.responses << ErrorInvalidToken
 end
diff --git a/src/storage.cr b/src/storage.cr
index 1e441b6..0df1f12 100644
--- a/src/storage.cr
+++ b/src/storage.cr
@@ -54,11 +54,11 @@ class DNSManager::Storage
 		Response::Success.new
 	end
 
-	def add_or_update_zone(user_id : Int32, domain : String) : IPC::JSON
+	def new_domain(user_id : Int32, domain : String) : IPC::JSON
 		# User must exist.
 		user_data = user_data_by_uid.get? user_id.to_s
 		unless user_data
-			Baguette::Log.warning "unknown user #{user_id} tries to add -or update- zone #{zone.domain}"
+			Baguette::Log.warning "unknown user #{user_id} tries to add domain #{domain}"
 			return Response::UnknownUser.new
 		end
 
@@ -66,7 +66,7 @@ class DNSManager::Storage
 			Response::DomainAlreadyExists.new
 		else
 			# Add the domain to the user's domain.
-			user_data.domains << zone.domain
+			user_data.domains << domain
 
 			# Actually write data on-disk.
 			update_user_data user_data