diff --git a/indra/llappearance/llavatarjoint.cpp b/indra/llappearance/llavatarjoint.cpp
index 353857bc9..5153debff 100644
--- a/indra/llappearance/llavatarjoint.cpp
+++ b/indra/llappearance/llavatarjoint.cpp
@@ -105,8 +105,9 @@ void LLAvatarJoint::setValid( BOOL valid, BOOL recursive )
 		for (child_list_t::iterator iter = mChildren.begin();
 			 iter != mChildren.end(); ++iter)
 		{
-			LLAvatarJoint* joint = (LLAvatarJoint*)(*iter);
-			joint->setValid(valid, TRUE);
+			LLAvatarJoint* joint = dynamic_cast<LLAvatarJoint*>(*iter);
+			if (joint)
+				joint->setValid(valid, TRUE);
 		}
 	}
 
@@ -138,8 +139,9 @@ void LLAvatarJoint::setVisible(BOOL visible, BOOL recursive)
 		for (child_list_t::iterator iter = mChildren.begin();
 			 iter != mChildren.end(); ++iter)
 		{
-			LLAvatarJoint* joint = (LLAvatarJoint*)(*iter);
-			joint->setVisible(visible, recursive);
+			LLAvatarJoint* joint = dynamic_cast<LLAvatarJoint*>(*iter);
+			if(joint)
+				joint->setVisible(visible, recursive);
 		}
 	}
 }
diff --git a/indra/llappearance/llavatarjointmesh.cpp b/indra/llappearance/llavatarjointmesh.cpp
index 4a5cff1dc..5099e5481 100644
--- a/indra/llappearance/llavatarjointmesh.cpp
+++ b/indra/llappearance/llavatarjointmesh.cpp
@@ -366,8 +366,9 @@ void LLAvatarJointMesh::setupJoint(LLAvatarJoint* current_joint)
 	for (LLJoint::child_list_t::iterator iter = current_joint->mChildren.begin();
 		 iter != current_joint->mChildren.end(); ++iter)
 	{
-		LLAvatarJoint* child_joint = (LLAvatarJoint*)(*iter);
-		setupJoint(child_joint);
+		LLAvatarJoint* child_joint = dynamic_cast<LLAvatarJoint*>(*iter);
+		if(child_joint)
+			setupJoint(child_joint);
 	}
 }
 
diff --git a/indra/llappearance/llpolyskeletaldistortion.cpp b/indra/llappearance/llpolyskeletaldistortion.cpp
index efdf5c577..3157cc965 100644
--- a/indra/llappearance/llpolyskeletaldistortion.cpp
+++ b/indra/llappearance/llpolyskeletaldistortion.cpp
@@ -154,13 +154,13 @@ BOOL LLPolySkeletalDistortion::setInfo(LLPolySkeletalDistortionInfo *info)
                 for (LLJoint::child_list_t::iterator iter = joint->mChildren.begin();
                      iter != joint->mChildren.end(); ++iter)
                 {
-                        LLAvatarJoint* child_joint = (LLAvatarJoint*)(*iter);
-                        if (child_joint->inheritScale())
-                        {
-                                LLVector3 childDeformation = LLVector3(child_joint->getScale());
-                                childDeformation.scaleVec(bone_info->mScaleDeformation);
-                                mJointScales[child_joint] = childDeformation;
-                        }
+					LLAvatarJoint* child_joint = dynamic_cast<LLAvatarJoint*>(*iter);
+					if (child_joint && child_joint->inheritScale())
+                    {
+                            LLVector3 childDeformation = LLVector3(child_joint->getScale());
+                            childDeformation.scaleVec(bone_info->mScaleDeformation);
+                            mJointScales[child_joint] = childDeformation;
+                    }
                 }
 
                 if (bone_info->mHasPositionDeformation)