Comment 63 for bug 330824

@Ted - these are the Jaunty fs/ext4 commits that are different then 2.6.28.9:

LP: #346194
bbf2bb7bd0a7efaaea309c88dc6bc7d1f89b7516 ext4: fix header check in ext4_ext_search_right() for deep extent trees.

Per your suggestion to ameliorate the delayed rename behavior:
0903d3a2925f3cffb78ca611c4e3356ac7ffef8a UBUNTU: SAUCE: (drop after 2.6.28) ext4: add EXT4_IOC_ALLOC_DA_BLKS ioctl
a4a01c495e3d445428015ff7f9825430e77f9567 UBUNTU: SAUCE: (drop after 2.6.28) ext4: Automatically allocate delay allocated blocks on close
f305d27b95849da130c3319e51054309c371e92a UBUNTU: SAUCE: (drop after 2.6.28) ext4: Automatically allocate delay allocated blocks on rename