RTE when using CrossFade

Scenario:

• I have a button with a custom skin, which only contains a BitmapImage.
• The BitmapImage has different "source" values depending on the button state.
• All source values are @Embeds.
• Transitions between states are animated using a CrossFade with the BitmapImage as target.
  (see attached SwitchViewButtonSkin.mxml as example)

Very infrequently, when hovering over or out of the button, the RTE posted below occurs.

I was able to create a test case (attached Test.mxml) where a CrossFade-effect on a BitmapImage with no size (0x0) causes such a RTE, but I think that the actual problem is, that the @Embed-image is not yet loaded at the time the CrossFade wants to capture a snapshot of the BitmapImage.

Actual Results:

ArgumentError: Error #2015: Invalid BitmapData.
at flash.display::BitmapData()
at spark.primitives.supportClasses::GraphicElement/http://www.adobe.com/2006/flex/mx/internal::captureBitmapData()[E:\dev\4.0.0\frameworks\projects\spark\src\spark\primitives\supportClasses\GraphicElement.as:3099]
at spark.effects::AnimateTransitionShader/getValueFromTarget()[E:\dev\4.0.0\frameworks\projects\spark\src\spark\effects\AnimateTransitionShader.as:281]
at mx.effects::Effect/http://www.adobe.com/2006/flex/mx/internal::captureValues()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\effects\Effect.as:1462]
at mx.effects::Effect/captureStartValues()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\effects\Effect.as:1364]
at mx.core::UIComponent/commitCurrentState()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\core\UIComponent.as:9778]
at mx.core::UIComponent/setCurrentState()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\core\UIComponent.as:9701]
at mx.core::UIComponent/set currentState()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\core\UIComponent.as:6087]
at spark.components.supportClasses::SkinnableComponent/commitProperties()[E:\dev\4.0.0\frameworks\projects\spark\src\spark\components\supportClasses\SkinnableComponent.as:428]
at spark.components.supportClasses::ButtonBase/commitProperties()[E:\dev\4.0.0\frameworks\projects\spark\src\spark\components\supportClasses\ButtonBase.as:735]
at mx.core::UIComponent/validateProperties()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\core\UIComponent.as:7772]
at mx.managers::LayoutManager/validateProperties()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\managers\LayoutManager.as:572]
at mx.managers::LayoutManager/doPhasedInstantiation()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\managers\LayoutManager.as:700]
at mx.managers::LayoutManager/doPhasedInstantiationCallback()[E:\dev\4.0.0\frameworks\projects\framework\src\mx\managers\LayoutManager.as:1072]

So it happens at the following line (wrong values passed to BitmapData constructor):

var bitmapData:BitmapData = new BitmapData(Math.ceil(rectBounds.width), Math.ceil(rectBounds.height), transparent, fillColor);

with the following values (from a live project, not the test case):

this spark.primitives.BitmapImage
transparent true
fillColor 0
useLocalSpace false
clipRect null
restoreDisplayObject false
oldDisplayObject null
topLevel mx.managers.WindowedSystemManager
rectBounds flash.geom.Rectangle
bottom 6710896
height 0
left 6711742.4
right 6711742.4
top 6710896
width 0
x 6711742.4
y 6710896
bitmapData null
m null

"rectBounds" looks quite wrong.

Expected Results:
no RTE

Workaround (if any):
no idea