Linkage betwen Otcl and C++ code: problem not resolved (be patient please)

[Luca Liberti <xliberti@tin.it>]

Hello everybody,
     I'm using ns 2.1b5.
Someone knows because NS doesn't  want to execute the linkage between the C++
code and Tcl code.
Look please this simple example and tell me what I miss.

~~~~
The error mesage is:

    (_o11 cmd line 1)
    invoked from within
"_o11 cmd hello"
    invoked from within
"catch "$self cmd $args" ret"
    (procedure "_o11" line 2)
    (SplitObject unknown line 2)
    invoked from within
"$p hello"
    (file "prova_otcl_linkage.tcl" line 4)     

~~~~
This is the Otcl script 

# file  "prova_otcl_linkage.tcl"
Class Agent/Prova -superclass Agent
set ns [new Simulator]
set p  [new Agent/Prova]
$p hello
exit 1

~~~~
This is the simple C++ code 

//  file  "prova_otcl_linkage.cc"
#include "agent.h"
#include <stdio.h>
#include "packet.h"
#include "tclcl.h"
#include "address.h"
#include "ip.h"

//-------- class definition -------------------------
class prova : public Agent {
public:
	prova();
        int command(int argc, const char*const* argv);  
};

//-------- Otcl linkage -------------------------
static class provaClass : public TclClass {
public:
	provaClass() : TclClass("Agent/Prova") {}
	TclObject* create(int, const char*const*) {
		return (new prova());
	}
} class_prova;
//---------------------------------


prova::prova() : Agent(PT_NTYPE)
{ 
    printf("@@@@@@@ I am here");
}

int prova::command(int argc, const char*const* argv)
{
	Tcl& tcl = Tcl::instance();
	if (argc == 2) {
		if (strcmp(argv[1], "hello") == 0) {
                        printf("C++ prova : hello I am here");
                        tcl.evalc("puts Otcl Agent/Prova: Hello I am here");
			return (TCL_OK);
		}
	}
	return (Agent::command(argc, argv));
}
//------------------------------------

Thanks in advance to all NS comunitty.
Luca Liberti