The catch is that you must fail the test the first time

“Come Back” Promotion

Here’s how to redeem your Cisco “Come Back” Exam:Register for an exam at full price. If you fail the exam, you may schedule a free retake of the same exam by entering the promotion code: COMEBACK at the time of registration.

IMPORTANT NOTE: Both the full-price exam and free Come Back retake must be scheduled and taken between April 15, 2008 and October 15, 2008, to qualify for this special promotion. Free exams may only be scheduled via the web. More…

UPDATE: It looks like there is another catch to this ;)  Quote from Cisco Certification Support:

The “Come Back” Promotion applies to candidates whose certifications have expired.
The first attempt must be paid, but the second is free. This promotion does not apply if you are currently certified.

Security Activity Bulletin:

Sebastian Muniz of CORE Security Technologies has announced that he will present a proof-of-concept rootkit for Cisco IOS devices.  Muniz stated that the proposed rootkit was not designed for any specific version of Cisco IOS and could be installed on a number of devices and versions, but this data has not been confirmed.  More….

Rootkits on Cisco IOS Devices:

Cisco Response

This is the Cisco PSIRT response to an issue that was disclosed by Mr. Sebastian Muniz of Core Security Technologies at the EUSecWest security conference on May 22, 2008.

No new vulnerability on the Cisco IOS software was disclosed during the presentation. To the best of our knowledge, no exploit code has been made publicly available, and Cisco has not received any customer reports of exploitation.  More…