Well, it appears the error is coming from config-int.php - although I'm not sure why since it's on a define() statement. You might consider turning off "notices" in your PHP.INI setup since it can produce unnecessary messages like these.
We also have this line in pp-inc.php:
error_reporting (E_ALL ^ E_NOTICE);
which could be added to the top of config-int.php to turn off these messages.
The only other thing I can find, which may or may not resolve the issue for your configurations, is to add quotes around the variables in the lines with define():
define( "MOBILE_CAT", -1 );
and do that for each line 31, 41-43, 49 and 56.
Please do not PM me for support or sales questions. Thank you for your understanding.