Chipmunk changing mass from STATIC_MASS

[PawApps]

Hello,

I have a wall that is set up as follows:

cpCCSprite *wall_bottom = [cpCCSprite spriteWithFile:@"wall_bottom.png"];
    cpShape *wall_bottom_shape = [sm addRectAt:ccp(field_position.y + [wall_bottom contentSize].width/2, field_position.x) mass:STATIC_MASS width:[wall_bottom contentSize].width height:[wall_bottom contentSize].height rotation:0.0f];
    wall_bottom.shape = wall_bottom_shape;
    [self addChild:wall_bottom];

Later (after a game over) I want the wall to fall away:

cpBodySetMass([wall_bottom shape]->body, 25.0f);

The shape (invisible) falls away, but the sprite (wall_bottom) stays put on the screen. Any ideas?

Note: using SpaceManager

Thanks

[PawApps]

Update for anyone that may find this thread in the future and wants the solution.

I don't understand the reasons behind it, but instead of changing the mass of a shape, I removed the shape from the space and added a new shape that looked identical, same position and all, but with the only difference being it had a mass. This looked and worked very well.

[sm removeShape:[wall_bottom shape]];
    cpShape *new_shape = [sm addRectAt:[wall_bottom position] mass:25.0f width:[wall_bottom contentSize].width height:[wall_bottom contentSize].height rotation:0.0f];
    wall_bottom.shape = new_shape;