Menu items which share a URL alias misbehave

In the process of trying out different image gallery modules I have several menu items in my primary menu which share names or path alias'. For example, acidfree lives at /gallery as does shazamgallery. Acidfree seems to have created several submenu items as well. No biggie, I didn't have both modules installed simultaneously ever.

The problem is that menu items which share a URL alias are all modified whenever a single one is. If I disable one they are all disabled (and all but one disappears from the list IIRC). Re-enabling the menu item makes the others reappear. Deleting one mades the other disappear though a peek in the "menu" table shows that it is still there, as garbage now.

It seems that menu items are only queried by their alias (which cannot be assumed unique) instead of using their ID. The end result is easy confusion.