Salve a tutti perche i controlli javascript non funzionanao sul mio sito quando lo apro con firefox?

ecco i controlli:
if (frm.nome.value==""){alert ("Insert your first name");document.frm.nome.focus();return false;}
else if (frm.cognome.value==''){alert ("Insert your last name");document.frm.cognome.focus();return false;}
else if (frm.posizione.value==''){alert ("Insert your position");document.frm.posizione.focus();return false;}
else if (frm.org.value==''){alert ("Insert your Organization/Affiliation name");document.frm.org.focus();return false;}
else if (frm.sex.value==''){alert ("Insert your sex");document.frm.sex.focus();return false;}
else if (frm.gg.value==''){alert ("Insert your birthday day");document.frm.gg.focus();return false;}
else if (frm.mm.value==''){alert ("Insert your birthday mounth");document.frm.mm.focus();return false;}
else if (frm.aa.value==''){alert ("Insert your birthday year");document.frm.aa.focus();return false;}
else if ((frm.indirizzo.value=='')&&(frm.indirizzo_lavoro. value=='')){alert ("Please insert home or/and office contact details");document.frm.indirizzo.focus();return false;}
else if ((frm.citta.value=='')&&(frm.citta_lavoro.value==' ')){alert ("Please insert home or/and office contact town");return false;}
else if ((frm.stato.value=='')&&(frm.stato_lavoro.value==' ')){alert ("Please insert home or/and office contact state");return false;}
else if ((frm.cap.value=='')&&(frm.cap_lavoro.value=='')){ alert ("Please insert home or/and office contact zip/post code");return false;}