System Information
Windows 8.1
NVIDIA GeForce GTX 660M - 2GB
i7-3740 QM @ 2.7GHz
16gb RAM

Blender Version
Broken: 2.69.0 r60995

Short description of error
When any value of a Compositing Node is keyframed everything works as expected. If that node now gets muted all keyframes of that node are cleared. when unmuting that node again keyframes are still gone. when pressing CTRL Z, the keyframes are back there (node is muted again) ... unmuting then won't clear the keyframes.

This Bug just affects compositing nodes and keyframes... shader nodes and texture nodes work fine, as well as drivers on compositing nodes don't get deleted.

Exact steps for others to reproduce the error
open node editor
switch to compositing nodes
tick "use nodes"
add any node (i confirmed this bug with mix, alpha over, invert, HSV, RGB Curver, so i guess all compositing nodes are affected)
while hovering over a numeric value press "i" to add a keyframe ==> turns yellow
mute that node by pressing "m" ==> turns grey

optional:
unmute that node by pressing "m" again ==> stays grey
CTRL Z ==> note is muted again, keyframes are back in position (fields are yellow)
unmute that node by pressing "m" again ==> keyframes stay there ==> field stays yellow