Link text ignored when creating a web link without specifying a protocol

Steps to reproduce

1. Edit/create a page/blog
2. Click on the insert link button
3. Select "Web link"
4. Enter "www.atlassian.com" in the address field
5. Enter "Atlassian" in the link text field
6. Click insert

Expected results

A link with the text "Atlassian" is inserted that links to "http://www.atlassian.com/"

Actual results

A link with the text "http://www.atlassian.com" is inserted that links to the same URL.