Insert Media Link in General Link breaks if parentheses is used

In Sitecore 6.6 (the issue is fixed from 7.0 and forward), there is an annoying bug, that causes the Insert Media Link dialog, if parentheses is used in the link description or the alternative text.

Here is how to reproduce it:

1. Install Sitecore 6.6 rev. 140410
2. Create a template with a general link field.
3. Create an item based on this template.
4. Click Insert Media Link, and select a media item.
5. Enter a link description and alternative text containing parantheses, and click OK to close the dialog.
6. Click Insert Media Link again, and watch the "Value cannot be null" exception.

If you happen to run into this issue, there is a workaround you can get from Sitecore Support - just contact them, and ask for the fix given out in the issue #434185 .

It is a small DLL and a zip file, so nothing fancy - but none the less, it works.