Menu item isn't created with 2 dashes in the first part of the path [#1123952]

I have a view with a page display and a path of resources-and-publications/publications. Adding a normal menu item to the Secondary Links menu does not work: it does not appear on the menu edit page (/admin/build/menu-customize/secondary-links) or in the site menu, though it is in the DB - an export of the rows in menu_router and menu_links is attached (broken.sql). I've compared this to the working version and the only difference is the missing dash (working version is working.sql). This could be a bug in the menu system, but it works as expected if I just create a menu item with the same path.

This seems only to be an issue when there are two dashes in the first part of the path. Any of the following will work normally:

Remove the dashes: resourcesandpublications/publications
Remove one dash: resources-andpublications/publications
Replace the path separator with a dash: resources-and-publications-publications
Three dashes before the path separator: resources-and-publications-etc/publications
Four dashes before the path separator (to make sure it wasn't "even number of dashes" that caused it): resources-and-publications-and-such/publications

It's also fine with dashes after the path separator: