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diff --git a/externals/grill/flext/examples/source/henon.cpp b/externals/grill/flext/examples/source/henon.cpp
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+/* 
+flext examples - henon
+
+Copyright (c) 2003 Thomas Grill (xovo@gmx.net)
+For information on usage and redistribution, and for a DISCLAIMER OF ALL
+WARRANTIES, see the file, "license.txt," in this distribution.  
+
+-------------------------------------------------------------------------
+
+This is a simple external featuring the chaotic Henon attractor.
+
+See also http://improv.sapp.org/doc/examples/synthImprov/henontune/henontune.html
+Thanks to David Casal for the pointer!
+
+*/
+
+// IMPORTANT: enable attribute processing (specify before inclusion of flext headers!)
+// For clarity, this is done here, but you'd better specify it as a compiler definition
+// FLEXT_ATTRIBUTES must be 0 or 1, 
+#define FLEXT_ATTRIBUTES 1
+
+
+// include flext header
+#include <flext.h>
+
+// check for appropriate flext version
+#if !defined(FLEXT_VERSION) || (FLEXT_VERSION < 401)
+#error You need at least flext version 0.4.1
+#endif
+
+
+class henon:
+	public flext_base
+{
+	FLEXT_HEADER_S(henon,flext_base,Setup)
+ 
+public:
+	// constructor 
+	henon(int argc,const t_atom *argv);
+
+protected:
+	void m_bang();
+	void m_reset() { x = y = 0; }
+
+	void m_alpha(float a) { alpha = a; }
+	void m_beta(float b) { beta = b; }
+	
+	float alpha,beta; 
+	float x,y;
+
+private:
+	static void Setup(t_classid c);
+
+	// method callbacks
+	FLEXT_CALLBACK(m_reset)
+	FLEXT_CALLBACK(m_bang)
+	FLEXT_CALLBACK_F(m_alpha)
+	FLEXT_CALLBACK_F(m_beta)
+
+	// define attribute callbacks for variables alpha and beta (with GET and SET properties)
+	FLEXT_ATTRVAR_F(alpha)
+	FLEXT_ATTRVAR_F(beta)
+};
+
+// instantiate the class 
+FLEXT_NEW_V("henon",henon)
+
+
+henon::henon(int argc,const t_atom *argv):
+	alpha(0),beta(0),x(0),y(0)  // initializations
+{ 
+	// define inlets
+	AddInAnything("reset,bang,...");  
+	AddInFloat("alpha");
+	AddInFloat("beta");
+	
+	// define outlets
+	AddOutFloat();  
+
+	// processing command line
+	if(argc == 2 && CanbeFloat(argv[0]) && CanbeFloat(argv[1])) {
+		// two float args
+		alpha = GetAFloat(argv[0]);
+		beta = GetAFloat(argv[1]);
+	}
+} 
+
+void henon::Setup(t_classid c)
+{
+	// register methods
+	FLEXT_CADDBANG(c,0,m_bang);  
+	FLEXT_CADDMETHOD_(c,0,"reset",m_reset);  
+
+	FLEXT_CADDMETHOD(c,1,m_alpha);
+	FLEXT_CADDMETHOD(c,2,m_beta);  
+
+	// register attributes
+	FLEXT_CADDATTR_VAR1(c,"alpha",alpha);  // register attribute "alpha" 
+	FLEXT_CADDATTR_VAR1(c,"beta",beta);  // register attribute "beta" 
+}
+
+// Trigger output
+void henon::m_bang()
+{
+	float _alpha_ = alpha*1.5f-2.5f;
+	float _beta_ = beta-0.5f;
+
+	float newx = 1 + _alpha_ * x * x + _beta_ * y;
+	float newy = x;
+	x = newx;
+	y = newy;
+
+	float output = (x + 1.0f)/2.0f;
+	if(output < 0)
+		output = 0;
+	else if(output > 1)
+		output = 1;
+	
+	// output value to outlet
+	ToOutFloat(0,output); // (0 stands for the outlet index 0)
+}