is_writable() doesn't work properly under Windows, phpbb_is_writable() should be used instead.
Fix for 3.0 in http://github.com/nickvergessen/phpbb3/compare/phpbb:develop-olympus...nickvergessen:ticket/9519
3.1 coming soon.
There are no other calls in 3.1, so the patch is the same for both.
Looks like at least in acm_*.php you have to check if the function is actually available before calling it.
Like this. http://tracker.phpbb.com/browse/PHPBB3-7901?focusedCommentId=28367&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#action_28367
The merge to 3.1 only contains the first commit, and the one to 3.0 got an email for each. Is that intended?
The merge contains all 4 commits for this ticket. See merge commit http://github.com/phpbb/phpbb3/commit/e4ff780c1370d9f743da0fffc70b98be0c7cfe92 I don't know about emails.