Within the Domino config database (domcfg.nsf) one can set a mapping for a custom "General Error" form to be displayed if such an error occours.
Unfortunately this mapping obviously doesn´t count for (non-database related) path errors.
In this case either:
a.) an ugly server error message with an 404 error is displayed or
b.) one has configured a setting within the notes.ini file
However, I´d wish that in EVERY case of an "General error", including path errors, the custom "General Error" form, configured in the Domino Config, should be displayed.
In this way there would be a uniform error page, which can be customized for different customers hosted on the same server!
Alternatively make a new notes.ini parameter like "HTTPHandlePathErrorsByDominoConfig=1".