diff --git a/htmlparser.js b/htmlparser.js
index e4275e3..da92232 100644
--- a/htmlparser.js
+++ b/htmlparser.js
@@ -31,9 +31,9 @@
 (function () {
 
 	// Regular Expressions for parsing tags and attributes
-	var startTag = /^<([-A-Za-z0-9_]+)((?:\s+[a-zA-Z_:][-a-zA-Z0-9_:.]+(?:\s*=\s*(?:(?:"[^"]*")|(?:'[^']*')|[^>\s]+))?)*)\s*(\/?)>/,
+	var startTag = /^<([-A-Za-z0-9_]+)((?:\s+[a-zA-Z_:][-a-zA-Z0-9_:.]*(?:\s*=\s*(?:(?:"[^"]*")|(?:'[^']*')|[^>\s]+))?)*)\s*(\/?)>/,
 		endTag = /^<\/([-A-Za-z0-9_]+)[^>]*>/,
-		attr = /([a-zA-Z_:][-a-zA-Z0-9_:.]+)(?:\s*=\s*(?:(?:"((?:\\.|[^"])*)")|(?:'((?:\\.|[^'])*)')|([^>\s]+)))?/g;
+		attr = /([a-zA-Z_:][-a-zA-Z0-9_:.]*)(?:\s*=\s*(?:(?:"((?:\\.|[^"])*)")|(?:'((?:\\.|[^'])*)')|([^>\s]+)))?/g;
 
 	// Empty Elements - HTML 5
 	var empty = makeMap("area,base,basefont,br,col,frame,hr,img,input,link,meta,param,embed,command,keygen,source,track,wbr");