diff -Nauwr Irrlicht/include/quaternion.h Irrlicht/include/quaternion.h
--- Irrlicht/include/quaternion.h	2005-08-20 22:17:44.000000000 +0200
+++ Irrlicht/include/quaternion.h	2005-09-16 14:38:34.000000000 +0200
@@ -150,13 +150,13 @@
 
 	if( diag > 0.0f )
 	{
-		scale = sqrtf(diag) * 2.0f; // get scale from diagonal
+		scale = 0.5f / sqrtf(diag); // get scale from diagonal
 
 		// TODO: speed this up
-		X = ( m(1,2) - m(2,1)) / scale;
-		Y = ( m(2,0) - m(0,2)) / scale;
-		Z = ( m(0,1) - m(1,0)) / scale;
-		W = 0.25f * scale;
+		X = ( m(2,1) - m(1,2) ) * scale;
+		Y = ( m(0,2) - m(2,0) ) * scale;
+		Z = ( m(1,0) - m(0,1) ) * scale;
+		W = 0.25f / scale;
 	}
 	else
 	{