If you hold down the sprint key while attempting to use the spacebar to jump the game ignores the input, and will only let you jump after you let go of the sprint key. Oddly enough if you bind the jump key to something other than the spacebar (like the C key for example) jumping works as it should.

To reproduce this issue:

1. join or create a world
2. hold down the sprint key and run
3. attempt to jump