--- a/jdk/src/share/classes/java/util/regex/Pattern.java	Wed Mar 04 09:26:41 2009 -0800
+++ b/jdk/src/share/classes/java/util/regex/Pattern.java	Fri Mar 20 16:22:59 2009 -0700
@@ -2567,7 +2567,8 @@
                 break;
             case '<':   // (?<xxx)  look behind
                 ch = read();
-                if (Character.isLetter(ch)) {     // named captured group
+                if (ASCII.isLower(ch) || ASCII.isUpper(ch) || ASCII.isDigit(ch)) {
+                    // named captured group
                     String name = groupname(ch);
                     if (namedGroups().containsKey(name))
                         throw error("Named capturing group <" + name