Not sure if this a bug...

[Quino]

You utter a prayer to your deity.
A grey tabby cat looks tired and weak.
--
Round later
--
You draw upon the powers granted by your god.
Soft blue light.
You failed to weaken a grey tabby cat.
--
And one more round later
--
You utter a prayer to your deity.
Soft blue light.
A grey tabby cat is already weakened.

Shouldn't it checked for mob is already affected by spell?