Magick++ bug with RoundJoin

I've got this problem using ImageMagick 6.3.3 on Slackware Linux.

This C++ code should produce two figures, identical apart from the type of 
line join.  The shape using MiterJoin is three sides of a square, as it 
should be.  The RoundJoin shape has an extra line from the square's top right 
corner to the bottom left.  I can work round this problem by tacking a 
PathMoveto onto the end of the path (as in the commented out line), although 
if I do that, the endcaps become round, even if I specify something else.


#include <Magick++.h>
#include <list>

using namespace std;
using namespace Magick;

void shape( Image& I, int x, int y, LineJoin J )
{
  list< VPath > path;
  list< Drawable > draw_list;
  path.push_back( PathMovetoAbs( Coordinate( x, y ) ) );
  path.push_back( PathLinetoRel( Coordinate( 0, 100 ) ) );
  path.push_back( PathLinetoRel( Coordinate( 100, 0 ) ) );
  path.push_back( PathLinetoRel( Coordinate( 0, -100 ) ) );
  //path.push_back( PathMovetoRel( Coordinate( 0, 0 ) ) );
  draw_list.push_back( DrawableFillColor( Color() ) );
  draw_list.push_back( DrawableStrokeWidth( 10 ) );
  draw_list.push_back( DrawableStrokeColor( Color( "black" ) ) );
  draw_list.push_back( DrawableStrokeLineJoin( J ) );
  draw_list.push_back( DrawablePath( path ) );
  I.draw( draw_list );
  return;
}

int main()
{
  Image I( Geometry( 250, 150 ),
	   Color( "white" ) );
  shape( I, 10, 25, RoundJoin );
  shape( I, 140, 25, MiterJoin );
  I.write( "test.png" );
  return 0;
}


-- 
Kevin Anthoney
[email protected]