Page publish/edit permissions lost when copying blog

I’ve been making duplicate copies of a blog, and been able to get everything working ok, except that all users have lost the ability to edit/publish pages.

I’m duplicating my WP install by taking the following steps…

1. copying all the tables and files
2. updating the wp-config with new table name prefix
3. changing the references to the old table names in the new wp_options and wp_usermeta tables. (eg. ‘wpold_capabilities’ becomes ‘wpnew_capabilities’)
4. updating .htaccess

As I said, everything works fine, except when I go to the edit pages (not posts) page the “Edit” and “Delete” links are not visible.

A few things I’ve worked out..

• the user roles in the wp_options table are exactly the same for both blogs.
• I’ve traced back through the code that works out user permissions, and the array ($capabilities) which gets evaluated by WP_User->has_cap() is missing a lot of values that are present in the original blog. (eg. ‘edit_others_pages’).

Is there a way to rebuild the permissions for users so that these values are present again?