I am trying to use page overlay with opacity. Everything is working fine but the opacity. The page overlay text is still solid color.

@page {
   @prince-overlay {
          content: "this text is overlaying the whole page and it needs 0.5 opacity";
	  font-family: Helvetica;
	  font-size: 36pt;
	  color: #C8C8C8;
	  transform: rotate(54.74deg);
	  overflow: hidden; 
	  text-overflow: ellipsis;
	  white-space: nowrap;
	  opacity: 0.5;
   }

Are you specifying a PDF profile that does not permit opacity, like early versions of PDF/A and PDF/X?

No, just using the default profile.

I think this may be a bug in opacity applied to margin boxes, we will investigate. Perhaps in the meantime you could workaround this problem by using an rgba color, like this:

color: rgba(200,200,200,50%);

Okay, thanks.