function check(form)
{
 if (form.name.value=="")
{
alert("Fill in your name or nick, please.");
form.name.focus();
return false;
}
 else if (form.odesilatel.value=="@")
{
alert("Fill in your email, please.");
form.odesilatel.focus();
return false;
}
else if (form.odesilatel.value=="")
{
alert("Fill in your email, please.");
form.odesilatel.focus();
return false;
}

else if (form.odesilatel.value!="")
{

  if (window.RegExp)
{
re = new RegExp("^[^.]+(\.[^.]+)*@([^.]+[.])+[a-z]{2,3}$");
if (!re.test(form.odesilatel.value))
{
alert("The email address is in incorrect form.");
form.odesilatel.focus();
return false;
}
else if (form.telo.value=="")
{
alert("Fill in your message, please.");
form.telo.focus();
return false;
}



}

}

else 
return true;
}