Redmine

(version 0.9.3)
I have a saved custom filter in my project. I opened it, then edited it, clicked "apply", then "save".( I expected the old filter to be updated instead of getting "provide name" field - that's a separate bug, btw). anyway, I provided the same old filter name and now I see two filters with identical names in the right panel, both of which are created by me.
shouldn't identical filter names be disabled? at least when they are created by the same user.