PPPOE settings error

[_igor_]

Its now a while i had to look at the PPPOE settings page, but now with the last failure i saw an old error which still exists:

When i set a "idle timeout" entry and save that, this entry disappears immediately. When i try to change other setting with "dial on demand" set, i get asked for an entry "idle timeout", which was set before. Tested various times, there is never set any idle timeout value.