1.4.4 character getting stuck on new world start up.

When starting a new world the character seems to be stuck in the block below it. You can't move or jump until you break the block below you.

Steps to Reproduce:
1. Create new world
2. survival, cheats on, starter chest on, world type default, random seed, structures on
3. start playing that world

It doesn't happen 100% of the time.