Error after upgrading from 1.0.2 to 1.0.5

[kotso]

No, It did not help but I found some more interesting info.

Problem is not in fast cgi, because any file I create in /var/www/ispcp/gui/ works fine

but index.php fails, after commenting out include of ispcp-lib.php index.php starts working, so problem is somewhere inside admin interface.

Please advice how can I do future debugging...