function validate_required(field,alerttxt)
{with(field)
{if(value==null||value=="")
{alert(alerttxt);return false;}
else{return true}}}
function validate_email(field,alerttxt)
{with(field)
{apos=value.indexOf("@");dotpos=value.lastIndexOf(".");if (apos<1||dotpos-apos<2) 
{alert(alerttxt);return false;}
else{return true;}}}
function validate_form(thisform)
{with(thisform)
{if(validate_email(email,"Not a valid e-mail address")==false)
{email.focus();return false;}
if(validate_required(S1,"Please enter a comment")==false)
{S1.focus();return false;}}}