Confirmed as there are two duplicates, it's clearly able to be reproduced, if only on amd64.
The bug is unusual in that the exception relates to a situation where you are trying to rename across a filesystem boundary.
This may be a result of /var folder being mounted in a different partition to /usr.
In any event, I will attach a fix shortly which should prevent this from occurring.
Confirmed as there are two duplicates, it's clearly able to be reproduced, if only on amd64.
The bug is unusual in that the exception relates to a situation where you are trying to rename across a filesystem boundary.
This may be a result of /var folder being mounted in a different partition to /usr.
In any event, I will attach a fix shortly which should prevent this from occurring.