How to prevent category hierarchy being broken in Admin

Hi there,

I have set up a couple of category hierarchies for my site. Categories selected from one tree indicate what kind of post a user is creating, categories selected from the second tree indicate who the post is about.

When first creating a post, the two trees show up in the Admin “Write Post” page’s category listing as expected, and I then do a few things with jQuery including ensuring that at least one of each is selected.

Unfortunately, if the post is later selected for editing, WordPress seems to list categories currently selected for this post first in the category listing. The remaining categories are then listed, but subsequently the hierarchy of categories is broken and my jQuery functionality can no longer work.

Is there a way to have WordPress display the category hierarchies unaltered, with current categories selected but located correctly in their trees? Via a plugin would be good, but I’d be prepared to make minor alterations to core files if absolutely necessary!

Thanks in advance

Alastair