When ever I publish the Kunena plugin via CB in the backend my profiles go blank, after turning on max error output this is the error it gives me, anyone have any ideas?

Notice: Use of undefined constant KUNENA_PATH_LIB - assumed 'KUNENA_PATH_LIB' in /home/sk8hell/public_html/beta/components/com_kunena/lib/kunena.config.class.php on line 20

Warning: require_once(KUNENA_PATH_LIB/kunena.debug.php) [function.require-once]: failed to open stream: No such file or directory in /home/sk8hell/public_html/beta/components/com_kunena/lib/kunena.config.class.php on line 20

Fatal error: require_once() [function.require]: Failed opening required 'KUNENA_PATH_LIB/kunena.debug.php' (include_path='.:/usr/local/lsws/lsphp5/lib/php') in /home/sk8hell/public_html/beta/components/com_kunena/lib/kunena.config.class.php on line 20

Also my current version is said to be 1.2.0 in the backend of community builder although I downloaded and installed the 1.2.1 package? Is this a known problem or could this be apart of the bigger problem, thanks guys for any help.

Sorry for my English ... google!

I installed 1.5 Kunena, cb 1.2.1, joomla 1.5.10 and i have is the exact same problem.
I tried to open the file kunena.config.class.php and I removed the offending line of code in question that contains the constant KUNENA_PATH_LIB in row 20.
It works!

But I state that are not expert in programming ... what is this line?