Index: src/wp-admin/includes/schema.php
===================================================================
--- src/wp-admin/includes/schema.php	(revision 34035)
+++ src/wp-admin/includes/schema.php	(working copy)
@@ -186,7 +186,7 @@
   ID bigint(20) unsigned NOT NULL auto_increment,
   user_login varchar(60) NOT NULL default '',
   user_pass varchar(64) NOT NULL default '',
-  user_nicename varchar(50) NOT NULL default '',
+  user_nicename varchar(60) NOT NULL default '',
   user_email varchar(100) NOT NULL default '',
   user_url varchar(100) NOT NULL default '',
   user_registered datetime NOT NULL default '0000-00-00 00:00:00',
Index: src/wp-admin/includes/user.php
===================================================================
--- src/wp-admin/includes/user.php	(revision 34035)
+++ src/wp-admin/includes/user.php	(working copy)
@@ -104,10 +104,11 @@
 
 	$errors = new WP_Error();
 
-	/* checking that username has been typed */
+	/* checking that username has been typed and user_login is less than 60 characters*/
 	if ( $user->user_login == '' )
 		$errors->add( 'user_login', __( '<strong>ERROR</strong>: Please enter a username.' ) );
-
+	elseif ( strlen( $user->user_login ) > 60 )
+		$errors->add( 'user_login', __( '<strong>ERROR</strong>: Please enter a username less than 60 characters.' ) );
 	/* checking the password has been typed twice */
 	/**
 	 * Fires before the password and confirm password fields are checked for congruity.
@@ -503,4 +504,4 @@
 
 Please click the following link to activate your user account:
 %%s' ), get_bloginfo( 'name' ), home_url(), wp_specialchars_decode( translate_user_role( $role['name'] ) ) );
-}
\ No newline at end of file
+}
Index: src/wp-admin/network/user-new.php
===================================================================
--- src/wp-admin/network/user-new.php	(revision 34035)
+++ src/wp-admin/network/user-new.php	(working copy)
@@ -89,7 +89,7 @@
 	<table class="form-table">
 		<tr class="form-field form-required">
 			<th scope="row"><label for="username"><?php _e( 'Username' ) ?></label></th>
-			<td><input type="text" class="regular-text" name="user[username]" id="username" autocapitalize="none" autocorrect="off" /></td>
+			<td><input type="text" class="regular-text" name="user[username]" id="username" autocapitalize="none" autocorrect="off" maxlength="60" /></td>
 		</tr>
 		<tr class="form-field form-required">
 			<th scope="row"><label for="email"><?php _e( 'Email' ) ?></label></th>
Index: src/wp-admin/user-new.php
===================================================================
--- src/wp-admin/user-new.php	(revision 34035)
+++ src/wp-admin/user-new.php	(working copy)
@@ -375,7 +375,7 @@
 <table class="form-table">
 	<tr class="form-field form-required">
 		<th scope="row"><label for="user_login"><?php _e('Username'); ?> <span class="description"><?php _e('(required)'); ?></span></label></th>
-		<td><input name="user_login" type="text" id="user_login" value="<?php echo esc_attr( $new_user_login ); ?>" aria-required="true" autocapitalize="none" autocorrect="off" /></td>
+		<td><input name="user_login" type="text" id="user_login" value="<?php echo esc_attr( $new_user_login ); ?>" aria-required="true" autocapitalize="none" autocorrect="off" maxlength="60" /></td>
 	</tr>
 	<tr class="form-field form-required">
 		<th scope="row"><label for="email"><?php _e('Email'); ?> <span class="description"><?php _e('(required)'); ?></span></label></th>
Index: src/wp-includes/user-functions.php
===================================================================
--- src/wp-includes/user-functions.php	(revision 34035)
+++ src/wp-includes/user-functions.php	(working copy)
@@ -1252,6 +1252,9 @@
 		return new WP_Error( 'existing_user_login', __( 'Sorry, that username already exists!' ) );
 	}
 
+	if ( strlen( $user_login ) > 60 )
+		return new WP_Error( 'user_login', __( 'Please enter a username less than 60 characters.' ) );
+
 	// If a nicename is provided, remove unsafe user characters before
 	// using it. Otherwise build a nicename from the user_login.
 	if ( ! empty( $userdata['user_nicename'] ) ) {