Chunk Loading Issues in 1.8-pre2 / corrupting world files

After updating 1.8-pre1 to 1.8-pre2 I got some problems with chunk loading.

Some of the chunks just never get loaded. It spreads like a disease, more an more chunks get corrupted with every server-restart.

Downgrading to 1.7.10 did not fix the missing chunks, so this bug probably corrupts the world files.

Server-log and Screenshot of the issue included.