Edit: I missed the changes to packs in the patch notes. We managed to get it fixed on our end. Sorry for the report.
After updating to snapshot 14w27b resource packs no longer load. We are running a small private server and have been keeping an custom updated 128 bit pack as the snapshots released. For the brief time we had 14w27a up and running this morning they were still loading fine.
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What are the changes in the resource packs? mine wont work either.