Server side script for NutiteqStreamedMap API

Hi,

I have implemented server side script to calculate BBOX for tileX,tileY. But it seems there's some mistake in calculating BBOX. I get tiles, but with Y-offset of more than 128 px. Can you please share me server side script to interpret NutiteqStream tile request URL, which calculates BBOX to get tiles for tileX,tileY?
Pseudo code algorithm is also fine.

Also I am pasting my code snippet which does tileX,tileY to BBOX conversion, incase you can point error -

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while(@xy){
$tileX = shift(@xy);

$tileY = shift(@xy);

$mapTopLeftX = $tileX*$resolution[$z]*$tileSizeInPixel-180;

$mapTopLeftY = 180-$tileY*$resolution[$z]*$tileSizeInPixel;

$mapBottomRightX=$mapTopLeftX + $resolution[$z]*$tileSizeInPixel;

$mapBottomRightY=$mapTopLeftY - $resolution[$z]*$tileSizeInPixel;

//tilecache URL http://server/cgi-bin/tilecache.cgi?LAYERS=LAYER_NAME&FORMAT=image%2Fpng&SERVICE=WMS&VERSION=1.1.1&REQUEST=GetMap&STYLES=&EXCEPTIONS=application%2Fvnd.ogc.se_inimage&SRS=EPSG%3A4326&BBOX=$mapTopLeftX,$mapTopLeftY,$mapBottomRightX,$mapBottomRightY&WIDTH=64&HEIGHT=64\n";
}

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