diff --git a/agunua/generate-trust-store.sh b/agunua/generate-trust-store.sh
index bb77c5d..9b3273f 100755
--- a/agunua/generate-trust-store.sh
+++ b/agunua/generate-trust-store.sh
@@ -48,7 +48,7 @@ for cert_file in ../certs/*; do
   port=$(expr "$cert_file" : '^../certs\/.*\:\([0-9]*\)\.pem$')
 
   # Hostname to punycode.
-  host=$(echo "$host" | idn)
+  host=$(echo "$host" | idn --allow-unassigned)
 
   # File for certificate/public key pinning
   if [ "$port" = 1965 ]; then
diff --git a/amfora/generate-trust-store.sh b/amfora/generate-trust-store.sh
index 0c408c2..9d9bb34 100755
--- a/amfora/generate-trust-store.sh
+++ b/amfora/generate-trust-store.sh
@@ -44,7 +44,7 @@ for cert_file in ../certs/*; do
   port=$(expr "$cert_file" : '^../certs\/.*\:\([0-9]*\)\.pem$')
 
   # Hostname to punycode.
-  host=$(echo "$host" | idn)
+  host=$(echo "$host" | idn --allow-unassigned)
 
   # Replace dots with slashes.
   host=$(echo "$host" | tr . /)
diff --git a/lagrange/generate-trust-store.sh b/lagrange/generate-trust-store.sh
index cb0f14f..1cfa8c3 100755
--- a/lagrange/generate-trust-store.sh
+++ b/lagrange/generate-trust-store.sh
@@ -41,7 +41,7 @@ for cert_file in ../certs/*; do
   host=$(expr "$cert_file" : '^../certs\/\(.*\)\:[0-9]*\.pem$')
 
   # Hostname to punycode.
-  host=$(echo "$host" | idn)
+  host=$(echo "$host" | idn --allow-unassigned)
 
   # Expiry date
   enddate=$(echo "$cert" | openssl x509 -enddate -noout | cut -d '=' -f 2)