Looks like IBM is following Suns lead by allowing free retakes. I just got this offer in the mail:
Dear Lotus Professional,
The IBM Lotus Professional Certification Team and Prometric would like to invite you to take advantage of our new Double-Take voucher program. With this exciting new initiative you may purchase a special voucher that allows you to retake an exam for no additional cost. All six Lotus Notes and Domino core exams are included as a part of this new program..
The program is only offered for a limited time. Double Take Vouchers will be available for purchase from now until September 30th, and must be redeemed no later than December 31, 2008.
Please visit the following IBM website for more details: www.ibm.com/certify/doubletake.shtml
Or, go directly to the Prometric website www.prometric.com/ibm/DoubleTake.htm to purchase your vouchers today!
Your IBM Lotus Professional Certification Team