diff --git a/letsencrypt/le_util.py b/letsencrypt/le_util.py
index 3eb4be0a7..d97d43dc6 100644
--- a/letsencrypt/le_util.py
+++ b/letsencrypt/le_util.py
@@ -298,18 +298,19 @@ def check_domain_sanity(domain):
     # Check if there's a wildcard domain
     if domain.startswith("*."):
         raise errors.ConfigurationError(
-            "Wildcard domains are not supported")
+            "Wildcard domains are not supported: {0}".format(domain))
     # Punycode
     if "xn--" in domain:
         raise errors.ConfigurationError(
-            "Punycode domains are not presently supported")
+            "Punycode domains are not presently supported: {0}".format(domain))
 
     # Unicode
     try:
         domain.encode('ascii')
     except UnicodeDecodeError:
         raise errors.ConfigurationError(
-            "Internationalized domain names are not presently supported")
+            "Internationalized domain names are not presently supported: {0}"
+            .format(domain))
 
     # FQDN checks from
     # http://www.mkyong.com/regular-expressions/domain-name-regular-expression-example/