Tweening a Sprites filter properties yields "n is undefined"

[petcarerx]

Setup:

//using a PIXI.Sprite:
sprite.filters=[new PIXI.filters.BlurFilter()];
//setup a tween for the blur property of the [0]'th filter, at first i tried { filters : [ { blur : 0.2 } ] } to no avail, then i tried:
tween 'from': { alpha: 0, y: 0, "filters[0]": { blur: 0.2 } }
'to':  { alpha: 1, y: -10, "filters[0]": { blur: 0.0 } }

That appears to work, but blows up the console with 'n is undefined' with below stack trace.

at u Line 1:4632 in pixi-tween.js
at u Line 1:4561 in pixi-tween.js
at value Line 1:7858 in pixi-tween.js
at value Line 1:6819 in pixi-tween.js
at value Line 1:9018 in pixi-tween.js