The only way to workaround this is to find the announcement id of the announcement and then hack the announcement edit URL to go to this announcement.
You can find the id of your announcement by querying the jiveannounce table in the database. The "announcementID" column is what you will want.
The URL for editting announcements looks like this:
Replace <id> with the announcmentID of your announcement from the database and you should be able to get to it and edit it.