diff --git a/kishib.py b/kishib.py
index 674ddac..0343ca0 100644
--- a/kishib.py
+++ b/kishib.py
@@ -249,6 +249,9 @@ def main():
 			usage('client')
 
 		host, = fixed
+		# Support internationalized domain names
+		host = host.encode('idna').decode()
+
 		client_pubkey = b'client'
 
 		server_pubkey = client(client_pubkey, host, port)