breadcrumb configuration doesn't save or error if invalid input given

configure a custom breadcrumb for one of your node types (ie admin/build/custom_breadcrumbs/node/edit/N)

enter something like this into the titles field:

Browse
[term]
[title]

enter something like this into the paths field:

browse
browse/[term-id]

- save it

- go back to the configuration page you just edited

notice that the setting weren't saved even though there was no indication of an error.

i vaguely recall submitting this same bug a long time ago, but i'm not certain.