Aaron's Bicycle Repair will not do any work on any bike (not even a flat!) with visibly damaged carbon fiber.

We will not work on repaired carbon fiber frames repaired by anyone other than Calfee or the original manufacturer. Calfee is the only place we recommend for carbon fiber repair. We will not work on repaired carbon fiber forks or componenets. Carbon fiber parts should be considered disposable!

We will not work on any steel framed bike with a carbon fiber seatpost. Carbon fiber seatposts are forbidden in steel frames due to the pinching force of the clamp. Carbon fiber seatposts require that the clamping force be opposite or 90 degrees from the slot. Also, carbon and steel will bond together worse than any aluminum post ever has. Carbon fiber steer tubes should NEVER have a star-fangled nut driven into them! Some Cannondale bikes have that done and that is the only exception we will work on. Industry standard for spacers under a stem is 40mm. Easton allows 50mm.

Trek's Official Carbon Warning
Specialized's Fork Installation Instructions
Easton's Fork Installation Instructions
Why Thompson doesn't use carbon fiber.
Busted Carbon Blog

If you have a carbon fiber steer tube, we STRONGLY recommend this aluminum insert. If you buy it we can install it.

Here is what Lon Kennedy, owner of Nova Cycle Supply (a wholesale supplier of Columbus carbon forks) has to say:
From an email:

From: Lon Kennedy
To: Tech Info at Nova
Sent: Monday, January 28, 2008 9:47 AM
Subject: Re: Carbon Steer Tube Damage?

Aaron,

Given the pictures, and not the part itself, my opinion is that the steerer appears to have cracks that would make the fork unsuitable for use.
Possible reasons for failure generally fall into 2 categories. My explanations are general and since I do not have the part in front of me to make a specific determination, are for your reference.

Rupture failures
1) Placement of the expander cap in an area not constrained or supported on the circumference by the stem or overtightening the expander cap.
As you are probably aware, general correct assembly practice is to make sure that the expander itself is surrounded by the stem to support it and prevent rupture failures.
Perhaps, too many spacers?
Snakebite failures

2) The stem has some areas of contact that are not carefully deburred as part a correct assembly routine. If the slot or the top or bottom or the stem is not properly deburred a crack can be initiated by the non-deburred area (sharp edge) scoring the steerer tube and initiating a crack.
My opinion is that the fork is unsafe to use given the appearance of cracks.

Hopefully this will help you in your assessment.

Lon/NOVA