PHP Parse Error While Installing ISPConfig

PHP Parse Error While Installing

Initial configuration

Operating System: Ubuntu 10.0.4 Server Edition 64bit

While installing ISPConfig 3.1 using CLI I get the following error message after the SSL option:-

Do you want a secure (SSL) connection to the ISPConfig web interface (y,n) [y]: n

PHP Parse error: syntax error, unexpected '[' in /usr/local/ispconfig/server/plugins-available/cron_plugin.inc.php on line 140

I have corrected this syntax error in the tmp folder but the same syntax error is in apache2_plugin.inc.php, mail_plugin.inc.php and probably many more plugins (I don't have the time to check all of them).