Here is a quick patch that just uses empty() to check the value in the $manifests instead of !. When you have more than one app server, you get improper index notices.
I'm having a hard time reproducing this issue - are you still having this problem on the current dev version?
This seems like a good patch that just in general better meets coding standards, but I also want to make sure any issues get resolved.
(i'm committing the patch from the OP as a style fix)
Automatically closed -- issue fixed for 2 weeks with no activity.
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