When a repeater is placed in direction f=0 facing a torch it flashes on for 1 redstone tick this does not occur in any other direction. I have videoed it at http://youtu.be/Z6NEc4_Eh8o
Linked issues
is duplicated by 8
3 more links
Pretty old bug, the repeater does not have to be facing a redstone torch either, it can be beside it, also, please remove environment info as this applies to any environment.