You can use this function:
function dxDrawBorderedText ( text, x, y, w, h, color, scale, font, alignX, alignY, clip, wordBreak, postGUI )
dxDrawText ( text, x - 1, y - 1, w - 1, h - 1, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false ) -- black
dxDrawText ( text, x + 1, y - 1, w + 1, h - 1, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x - 1, y + 1, w - 1, h + 1, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x + 1, y + 1, w + 1, h + 1, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x - 1, y, w - 1, h, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x + 1, y, w + 1, h, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x, y - 1, w, h - 1, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x, y + 1, w, h + 1, tocolor ( 0, 0, 0, 255 ), scale, font, alignX, alignY, clip, wordBreak, false )
dxDrawText ( text, x, y, w, h, color, scale, font, alignX, alignY, clip, wordBreak, postGUI )
end