function validation(contact_form)
{

if(""==document.forms.contact_form.name.value)
{
alert("Please enter your full name.");
return false;
}

if(""==document.forms.contact_form.telephone.value)
{
alert("Please enter your telephone number.");
return false;
}

if(""==document.forms.contact_form.fax.value)
{
alert("Please enter your fax number.");
return false;
}

if(""==document.forms.contact_form.subject.value)
{
alert("Please enter a subject.");
return false;
}

if(""==document.forms.contact_form.eaddress.value)
{
alert("Please enter your email address.");
return false;
}

if(""==document.forms.contact_form.Comment.value)
{
alert("Please enter a comment");
return false;
}
}