Error on activation

SYSTEM INFO

Database schema Up to date
File system Writable (public download method)
GD library bundled (2.0.28 compatible)
MySQL database 4.1.21
PHP 5.1.6
Unicode library PHP Mbstring Extension
Web server Apache

ERROR SHOWS 3 TIMES:

* warning: Missing argument 3 for privatemsg_send() in /home/public_html/modules/privatemsg/privatemsg.module on line 523.
* warning: Missing argument 3 for privatemsg_send() in /home/public_html/modules/privatemsg/privatemsg.module on line 523.
* warning: Missing argument 3 for privatemsg_send() in /home/public_html/modules/privatemsg/privatemsg.module on line 523.

name description release major minor cvstag cvsid
taxonomy_theme Map themes to nodes, taxonomy vocabs/terms or Drupal pathes/path aliases. 5.x-1.0 1.48
avatar_gallery Provides a block which is a clickable JPEG of all user's avatars, with their names placed under the picture. 5.x-1.x-dev
buddylist Users add other users to their buddylists. 5.x-1.x-dev
DRUPAL-5 1.68.2.7
Allows you to structure your site and categorize content. 4.7.x-1.x-dev localizer , subscriptions 1.62.2.1, systeminfo 1.14.4.1, video_customfields , video_params , video , widgeditor 1.1, contemplate 1.8
cck Allows administrators to define new content types. 5.x-1.2 DRUPAL-5--1-2 content 1.90.2.25, fieldgroup 1.1.4.12, nodereference 1.39.2.3, number 1.34.2.6, optionwidgets 1.10.2.3, text 1.41.2.7, userreference 1.30.2.6
cck_field_perms Allows admin to restrict create and update access on specific cck fields. 5.x-1.4 DRUPAL-5--1-4 1.3.2.8
computed_field Allows the user to define computed values in custom content types. 5.x-1.1 1.14
cre A backend for engine for and api for recommendations of any piece of content 5.x-1.0
DRUPAL-5-0 cre 1.15.2.2, node_recommendation 1.1.2.1
date Defines a date/time field type and a date api. 5.x-1.1 DRUPAL-5--1-1 1.32.2.10
email Defines an email field type for cck 5.x-1.x-dev 1.9
fivestar A simple five-star voting widget for nodes. 5.x-1.3 DRUPAL-5--1-3 1.2.2.1
imagefield Defines an image field type. 5.x-1.x-dev 1.30.2.2
imce An image/file uploader and browser supporting personal directories and user quota. 5.x-1.x-dev DRUPAL-5 1.8.2.25
link Defines simple link field types. 5.x-1.3
DRUPAL-5--1-4 1.20.2.2
mimemail E-mail with HTML and attachments 5.x-1.x-dev DRUPAL-5 1.14.2.1
og Enable users to create and manage their own 'groups 5.x-1.0 DRUPAL-5--1-0 1.298.2.26
page_title Enhanced control over the page title (in the tag). 5.x-1.x-dev
privatemsg Allow private messages between users 5.x-1.x-dev 1.70.2.1
releasemonitor Site Administrator Module that monitors releases of installed contributed projects. 5.x-1.x-dev 1.40
send Send to friend 5.x-1.x-dev DRUPAL-5 1.28.2.2
similar Displays a block with the most similar nodes to the currently viewed one, based on the title and body fields, for sites using MySQL MyISAM tables. 5.x-1.0 1.7
tagadelic Tagadelic makes weighted tag clouds from your taxonomy terms. 5.x-1.x-dev 1.36
usernode Automatically creation and 5.x-1.x-dev
DRUPAL-5 1.12.2.5
userpoints Resets all userpoints on the site. 5.x-1.1 DRUPAL-5--1-1 1.44.2.1
user_register_notify Notifies administrator of new user registrations. 5.x-1.x-dev 1.2
views RSS plugin for the views feed selector argument. 5.x-1.5 DRUPAL-5--1-5 views_rss 1.12.2.3, views_theme_wizard 1.11.2.3, views_ui 1.44.2.6, views 1.166.2.6
votingapi Provides a shared voting API for other modules. 5.x-1.2 1.40
votingapi_field Provides voting and ranking fields. 5.x-1.x-dev
path_image A module to provide an image file within a block dependant upon the Drupal path 5.x-1.0 DRUPAL-5--1-0 1.4.2.4
taxonomy_access Access control for user roles based on taxonomy categories. 5.x-1.x-dev 1.102
notify Enables notifications of new content and comments by e-mail. 5.x-1.x-dev 2.67

RE: if you change FILTER_FORMAT_DEFAULT to 0 on that line, any change?

if you mean replace this variable with the charater zero, no this doesnt change anything.

the error shows up on the administer/by-module page
also shows up 3 times when i run the check in the release monitor module
admin/settings/releasemonitor

now running 5.1, same error.

--

just updated to the Jan 30th version and the line switched to 524 as previous poster noted.

*** adding an X to the function name stops the error.