diff --git a/docs/config_naming.html b/docs/config_naming.html
index 859901bb8..5cefcbf77 100644
--- a/docs/config_naming.html
+++ b/docs/config_naming.html
@@ -74,7 +74,7 @@
         <tr>
           <td><span class="code">PackageName</span></td>
           <td>packages</td>
-          <td><span class="default">^[a-z]+(\\.[a-zA-Z_][a-zA-Z_0-9]*)*$</span></td>
+          <td><span class="default">^[a-z]+(\\.[a-zA-Z_][a-zA-Z0-9_]*)*$</span></td>
         </tr>
         <tr>
           <td><span class="code">ParameterName</span></td>
diff --git a/src/checkstyle/com/puppycrawl/tools/checkstyle/checks/PackageNameCheck.java b/src/checkstyle/com/puppycrawl/tools/checkstyle/checks/PackageNameCheck.java
index 888a93cd1..6eb941ac0 100644
--- a/src/checkstyle/com/puppycrawl/tools/checkstyle/checks/PackageNameCheck.java
+++ b/src/checkstyle/com/puppycrawl/tools/checkstyle/checks/PackageNameCheck.java
@@ -70,7 +70,7 @@ public class PackageNameCheck
         // Uppercase letters seem rather uncommon, but they're allowed in
         // http://java.sun.com/docs/books/jls/
         //   second_edition/html/packages.doc.html#40169
-        super("^[a-z]+(\\.[a-zA-Z_][a-zA-Z_0-9]*)*$");
+        super("^[a-z]+(\\.[a-zA-Z_][a-zA-Z0-9_]*)*$");
     }
 
     /** @see com.puppycrawl.tools.checkstyle.api.Check */