Salve,
posto qui perchè credo si tratti di un problema di Javascript, o al massimo di configurazione di browser . Però se ritenete che sia da spostare in php, fate pure. Grazie
Arrivo al punto , sto provando uno script che ho trovato qui nel sito , precisamente: questo
http://www.html.it/articoli/2269/esempio10.htm

Ecco il codice:

Codice PHP:
<script type="text/javascript" language="javascript" src="editor/editor.js">
                        
</script>                                  
                                <body onload="load();">
                                    <div id="formArticoli">
                                    <form action="getTextPage.php" method="POST" id="formEditArea" onsubmit="pulisciCodice();">
                                        <input type="hidden" name="codicePulito"/>
                                        <iframe src="" id="editArea" name="editArea" width="300" frameborder="0"></iframe>

                                        <div id="pulsantiera">
                                        [url="javascript:void();"][img]editor/img/corsivo.gif[/img][/url]

                                        [url="javascript:void();"][img]editor/img/grassetto.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/sottolineato.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/link.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/allineadestra.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/allineasinistra.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/allineacentro.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/giustifica.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/listaordinata.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/lista.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/undo.gif[/img][/url]
                                        [url="javascript:void();"][img]editor/img/redo.gif[/img][/url]
                                        <select onchange="applicaComando('formatblock',this.options[this.selectedIndex].value);">     
                                        <option>Scegli formato</option>
                                        <option value="h1">Titolo Grande</option>
                                        <option value="h2">Titolo Medio</option>
                                        <option value="h3">Titolo Piccolo</option>
                                        <option value="p">Paragrafo</option>
                                    </select>
                                    <select onchange="applicaComando('forecolor',this.options[this.selectedIndex].value);">     
                                        <option>Scegli un colore</option>
                                        <option value="#00FF00">Verde</option>
                                        <option value="#FF0000">Rosso</option>
                                        <option value="#0000FF">Blu</option>
                                        <option value="#000000">Nero</option>
                                        <option value="#990000">Rosso Mattone</option>
                                    </select>
                                    

                                </div>
                                
                                <input type="submit" value="salva"/>
                                    <input type="reset" name="reset" value="cancel">
                            </form>
                        </div>
                        </body>
</html> 
la pagina javascript, editor.js :

Codice PHP:
function AttivaFrame(iFrameID){
if (
document.getElementById(iFrameID).contentDocument){  
//Mozilla
return document.getElementById(iFrameID).contentDocument;
} else {
//Internet Explorer
return document.frames[iFrameID].document;
}
}
function 
applicaComando(cmdStr,valCmdStr){
if (!
document.getElementById("editArea").contentDocument){
switch(
valCmdStr){
case 
"h1":
valCmdStr "heading 1";
break;
case 
"h2":
valCmdStr "heading 2";
break;
case 
"h3":
valCmdStr "heading 3";
break;
case 
"p":
valCmdStr "paragraph";
break;
}
}
AttivaFrame("editArea").execCommand(cmdStr,false,valCmdStr);

function 
aggiungiLink(){
var 
linkURL prompt("Inserisci il link da aggiungere:""");
AttivaFrame("editArea").execCommand("createlink",false,linkURL); 
}    
function 
vediCodice(){
var 
contenuto AttivaFrame("editArea").body.innerHTML;
document.getElementById("codice").innerHTML contenuto.replace(/</g,"&lt;");
                                         }
                                         function 
pulisciCodice(){
                                         var 
contenuto AttivaFrame("editArea").body.innerHTML;
                                         
contenuto contenuto.replace(/<br\>/gi,"
"
);
                                        
contenuto contenuto.replace(/(<p\>)(.*)(<\/p\>)/gi,"

$2</p>"
);
                                        
contenuto contenuto.replace(/<\a/gi,"<a");
                                        
contenuto contenuto.replace(/<\/a\>/gi,"</a>");
                                        
contenuto contenuto.replace(/<\div\>/gi,"<div>");
                                        
contenuto contenuto.replace(/<\/div\>/gi,"</div>");
                                        
contenuto contenuto.replace(/(<strong\>)(.*)(<\/strong\>)/gi,"<span style=\"font-style: bold;\">$2</span>");
                                        
contenuto contenuto.replace(/(<ul\>)(.*)(<\/ul\>)/gi,"<ul>$2[/list]");
                                        
contenuto contenuto.replace(/(<li\>)(.*)(<\/li\>)/gi,"[*]$2");
                                        
//internet explorer    
                                        
contenuto contenuto.replace(/(<font )(color)(=)(#?([A-Fa-f0-9]){3}(([A-Fa-f0-9]){3})?)(>)(.*)(<\/font\>)/gi,"<span style=\"$2:$4;\">$9</span>"); 
                                        
contenuto contenuto.replace(/(<)(align)(=)([A-Za-z]*)(>)(.*)(<\/p\>)/gi,"<div style=\"text-align: $4;\">$6</div>");
                                        
contenuto contenuto.replace(/(<em\>)(.*)(<\/em\>)/gi,"<span style=\"font-style: italic;\">$2</span>");
                                        
//opera
                                        
contenuto contenuto.replace(/(<font )(color)(=\")(#?([A-Fa-f0-9]){3}(([A-Fa-f0-9]){3})?)(\")(>)(.*)(<\/font\>)/gi,"<span style=\"$2:$4;\">$10</span>"); 
                                        
contenuto contenuto.replace(/(<div )(align)(=\")([A-Za-z]*)(\")(>)(.*)(<\/div\>)/gi,"<div style=\"text-align:$4;\">$7</div>");        
                                        
contenuto contenuto.replace(/(<i\>)(.*)(<\/i\>)/gi,"<span style=\"font-style: italic;\">$2</span>");
                                        
                                        
document.getElementById("codicePulito").value contenuto;    
                                        } 

e una semplice paginetta di test lato server, in php :

getTextPage.php :

Codice PHP:
 echo $_POST['codicePulito']; 


ecco , il problema è che mi gira solo con Opera, ma non con Firefox !!! Penso che il codice sia giusto e Firefox non dovrebbe avere problemi con lo script. forse ho qualcosa di sbagliato nella configurazione di Firefox ?
Sarà ma non riesco a cavarne piedi...

ecco i dati:
Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.8.1.6) Gecko/20061201 Firefox/2.0.0.6 (Ubuntu-feisty)
Opera : Version 9.23