(EDIT: Removed the confusion about whether deleted questions are editable, and added some details)
When I start editing a deleted question, after about a minute the "Save Edits" button dynamically grays out. The page shifts down, and it looks like it's made space for an orange information bar along the top (like the "this is your first time here" alert), only nothing is displayed:
This only happens after I've started editing (just adding a space at the end of the post is sufficient); if I sit on the page and don't change the post text the button stays enabled. If I submit changes before the button grays out everything works fine. It looks like the button is disabled after the browser tries to post to http://meta.stackoverflow.com/posts/56804/edit-activity-heartbeat
I'm using Firefox 3.6.3 on Linux, but this also happens using Chromium