After doing much research, I found the fix for it. I have included files in the zip file which fix this problem for you if you are on a Windows based Web Server and running SMTP as your email application to send mails from the web server.
This fix only modifies the user.php file (for the welcome email upon registration that includes the user's password, and lost password retrieval) and the Recommend Us file (for recommending your site to other users and sending news article links to other users.)
The documentation in the zip file explains alot of information about this.
I hope this will assist in bringing it to the attention of developers to hopefully add the small extra /r in front of their /n in the mail functions so that it would look like: /r/n to solve this carriage return problem for us Windows users.
I have already posted this topic in the postnuke dev groups on yahoo.
Here's the file:
Postnuke SMTP for Windows Fix
You do not need this file if you are not having problems! This is only really intended for Windows machines running IIS or Apache and php that have the problem as I have stated above.
-Havoc
http://3dhavoc.net
http://wolfenstein.3dhavoc.net
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