--- a/modules/libpr0n/src/imgFrame.cpp
+++ b/modules/libpr0n/src/imgFrame.cpp
@@ -793,17 +793,17 @@ void imgFrame::GetImageData(PRUint8 **aD
 
 PRBool imgFrame::GetIsPaletted() const
 {
   return mPalettedImageData != nsnull;
 }
 
 PRBool imgFrame::GetHasAlpha() const
 {
-  return mFormat != gfxASurface::ImageFormatARGB32;
+  return mFormat == gfxASurface::ImageFormatARGB32;
 }
 
 void imgFrame::GetPaletteData(PRUint32 **aPalette, PRUint32 *length) const
 {
   if (!mPalettedImageData) {
     *aPalette = nsnull;
     *length = 0;
   } else {