Question of Mirror

Why I mirror the 2D model of Player,the collider of weapon is wrong?The weapon is binded at joint of Player.

PS:I mirror the 2D model by change transform.localScale.x = -1.The image is here http://forum.unity3d.com/viewtopic.php?t=42552&highlight=mirror+collider

Are you setting the scale to -1 in the inspector or with a script? Does the weapon have a mesh collider or a primitive collider (box, sphere, capsule)?

My weapon have BoxCollider,I change the model with script.