git: fatal error: `chdir’ failed: permission denied.

Problem
Trying to use the heroku gem to clone a project and do local modifications I got the following error:

Solution
It turns out that in Mandriva, when using:

what gets installed is the ‘GNU Interactive Tools’ that has nothing to do with the git version control system.
So make sure you first uninstall the git installed:

and then install the Git – Fast version control system, by doing:

You should then be able to clone a heroku application:

Ext.ux.grid has no properties error

Problem
Trying to use ExtJS with RubyOnRails on Heroku, gives the following error and a blank page in Firebug.

Solution
In Heroku, you will probably have to manually upload the files from the ExtJS library, as well as the ext_scaffold plugin.
When you do that, two files that ext_scaffold needs, and which they should be located in ext_scaffold/assets/javascripts should be copied to public/javascripts.
The files are: