From John Clayton's ESPN blog:

The 49ers are comfortable moving in a different direction if tight end Vernon Davis is gone before they pick sixth. They love linebacker A.J. Hawk and would fit him into their 3-4 scheme. They still have the ability to add to their defense with the 22nd pick and would like to get a big cornerback. Antonio Cromartie would be ideal. Still, Davis would be perfect for Alex Smith and the 49ers offense. He doesn't have the strongest arm, so adding a tight end who affords him easier throws in the middle of the field will make him a better quarterback.