boolean error

I am getting this in the error log file:
ERROR: Bad boolean external representation
'<font >color=red><b>YES></b></font>'

The code that is generating the message is all within the php delimiters
(entire file) and appears several times as follows:

if($r1==0 || $r2==0) {
    if($archived=='Y') {
        $archived="<font color=red><b>YES</b></font>";
    }
;;;

select wares.ware_id,wares.name,category.name,unit_size,
        qty_per_shipping_unit,supplier.name,sku,
        case when wares.archived='t' then '<font color=red><b>YES</b></font>'
else wares.archived end as archived,
        trademark.name
    from wares,category,wares_category,supplier_wares,supplier,trademark
    where wares.ware_id=wares_category.ware_id and
        category.category_id=wares_category.category_id and
        wares.ware_id=supplier_wares.ware_id and
        supplier_wares.supplier_id=supplier.supplier_id and
        wares.trademark_id=trademark.trademark_id";
I do not understand what is wrong? (This apparently worked fine in the
original online web site.)
Does anyone understand this?
Philip Jourdan