Link button URLs not processed properly after save

When using the "Link" button in the editor, URLs with some RFC 3986 legal characters are not saved correctly. They display and click through as expected when in the editor, but when you "preview" or save the page, the links are broken or are not clickable.

Steps to reproduce:
1. Edit a page in Confluence
2. Add the following URL or something similar with extended characters in it:
https://host.domain.com/q/22746274/run.report_html?comment_to_include_le_items=&outcome_start_date='2013-02-20'&offers_app=something
3. Click "Preview" or "Save" and hover over the link that was created. No URL displays in the browser and the link is not clickable.