To replicate, place a repeater and a comparator facing away from the same block. Quickly place and destroy a redstone block in that space. The repeater will turn on, but the comparator won't. Direction and mode of repeater/comparator don't affect this bug.
Environment
Operating system: OSX 10.9.5
Java Version: 1.6.0_65
Mojang can you explain why this is intended? Why should repeaters accept different types of pulses than comparators?