Hello,
I found a way to make Thunar display a folder as a symbolic link.
How to reproduce this bug:

Open a Terminal:
$mkdir subrep foo
$cd subrep
$ln -s ../foo foo

Then, open Thunar and go to the "subrep" folder.
Then, in the terminal:
$rm foo
$mkdir foo

subrep/foo is now a folder, but for Thunar, it's still a symbolic link. You can right click on the folder -> properties, the Type is "link to ../foo" (I'm using a French version of Thunar, I hope I did the correct translation).

It also work for a symbolic link to appears as a folder.