On some sites the tool prompts a validation message that between 2 and 100 characters are required for the description when a default description exists.
Adding extra characters does not help but deleting the description and pasting in a new one does work
This appears to be an issue in FF 3.6.13 and ie 8
Example => http://web001.focul.net/Public/linksharing/irt_focul.nsf/Document.xsp?documentId=109FD405F4122621802578470038CBA3