Problem fixed and uploaded to SVN repository.
GTK2 was detected incorrectly and it used some units from GTK1 causing that incompatible args error.

Problem compiling from lazarus v0.9.22 and gtk2.

/home/dualcore/local/lazarus/paquetes/Imaging/Source/ImagingComponents.pas(834,81) Error: Incompatible type for arg no. 2: Got "GDK2.PGdkGC", expected "GDK.PGdkGC"

Line:

  gdk_draw_rgb_32_image(TDeviceContext(Dest).Drawable, TDeviceContext(Dest).GC,
      DstX, DstY, SrcWidth, SrcHeight, GDK_RGB_DITHER_NONE,
      @PLongWordArray(ImageData.Bits)[SrcY * ImageData.Width + SrcX], ImageData.Width * 4);