Edit link does not set the edited page correctly when the reference is relative

Typing the following in a document in the Main space

[[link>>WebHome]]

results in a correct link, to the desired page. Editing the document in wysiwyg mode, and opening the link edit wizard does not position the explorer tree on the correct page (Main.WebHome), the input of the explorer being "WebHome".

The same thing happens for links to attached files, if they're referred by

[[file>>attach:filename.ext]]

they are not edited correctly in the explorer tree.