diff --git a/lib/utils.js b/lib/utils.js
index 7e9ebed..cc20f8d 100644
--- a/lib/utils.js
+++ b/lib/utils.js
@@ -2,7 +2,8 @@
 
 var path = require('path');
 var homeRe = new RegExp("^~(\\/|\\\\|\\" + path.sep + ")");
-var re = /^[a-zA-Z0-9\.\-]+$/;
+// very basic check. Allows *.example.com.
+var re = /^[a-zA-Z0-9\.\*\-]+$/;
 var punycode = require('punycode');
 var promisify = (require('util').promisify || require('bluebird').promisify);
 var dnsResolveMxAsync = promisify(require('dns').resolveMx);
diff --git a/package.json b/package.json
index 09d5851..704a2ce 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "greenlock",
-  "version": "2.2.5",
+  "version": "2.2.6",
   "description": "Let's Encrypt for node.js on npm",
   "main": "index.js",
   "scripts": {