Unable to upgrade to 1.1.1: Class 'ZIPARCHIVE' not found

After a very difficult upgrade from 1.0 to 1.1 (I must raz my original install and start from full 1.1) I receive an error while I try to upgrade to 1.1.1:

Fatal error: Class ‘ZIPARCHIVE’ not found in /home/ovh/www/piwik/core/Unzip.php on line 28

Note: 1.1 encounter strange behaviors:

Under Safari Mac, sometime data are correctly shown sometime not
Under Firefox Mac, is better but not every time

Whatever the navigator, it’s less fast and smoothie than with 1.0

Refresh your browser cache and try again?

You shouldn’t have had to start from scratch in 1.1, there was not a bug that prevented from keeping your data (only display bugs)

Same issue after cache dump.

I had the same issue with the automatic upgrade install. Tried the manual installation and all went well! This was done on my home based local server.

Sorry, some versions of php have a bug when using:

if (defined('ZIPARCHIVE:ER_OK'))

This is fixed in 1.1.1. If you’re still running 1.1, you can apply this patch:

Thanks for the tip!