Aegir installation issue While installing Aegir in a VM, during the hostmaster installation, I got the following error:

Do you really want to proceed with the install (y/n): y  
PROVISION_SITE_INSTALLED                                             [error]  
The external command could not be executed due to an application     [error]  
error.  
Drush command terminated abnormally due to an unrecoverable error.   [error]  
Error: Unsupported operand types in  
/var/aegir/drush/includes/environment.inc, line 916  


Drush version 4.5
Here is an issue on Drupal Groups: http://groups.drupal.org/node/96639.

Possible solutions:


Check if your system is Ubuntu (the installation script assumes that
it is)
Remove everything in /var/aegir and run the installation script again.
Run 'mysql_secure_installation' command and finish it successfully. Aegir
checks for security flaws during installation and block it if, for
example, you have anonymous users enabled in mysql.