diff -rup gimp-2.3.14-original/plug-ins/common/tiff.c gimp-2.3.14-patch/plug-ins/common/tiff.c
--- gimp-2.3.14-original/plug-ins/common/tiff.c	Tue Jan 23 11:16:01 2007
+++ gimp-2.3.14-patch/plug-ins/common/tiff.c	Thu Jan 25 14:25:54 2007
@@ -2225,6 +2225,15 @@ save_image (const gchar *filename,
        return FALSE;
     }
 
+  if (COMPRESSION_CCITTFAX3 == compression || COMPRESSION_CCITTFAX4 == compression)
+  {
+     if (1 != bitspersample || 1 != samplesperpixel)
+     {
+        g_message("Only monochrome pictures can be compressed with \"CCITT Group 4\" or \"CCITT Group 3\".");
+        return FALSE;
+     }
+  }
+
   /* Set TIFF parameters. */
   TIFFSetField (tif, TIFFTAG_SUBFILETYPE, 0);
   TIFFSetField (tif, TIFFTAG_IMAGEWIDTH, cols);
@@ -2492,6 +2501,8 @@ save_dialog (gboolean alpha)
                                     _("_Pack Bits"), COMPRESSION_PACKBITS, NULL,
                                     _("_Deflate"),   COMPRESSION_DEFLATE,  NULL,
                                     _("_JPEG"),      COMPRESSION_JPEG,     NULL,
+                                    _("CCITT Group _3 fax"), COMPRESSION_CCITTFAX3, NULL,
+                                    _("CCITT Group _4 fax"), COMPRESSION_CCITTFAX4, NULL,
 
                                     NULL);
 
