--- otvgsub.c~	2007-08-10 16:27:31.000000000 -0700
+++ otvgsub.c	2007-08-10 16:27:31.000000000 -0700
@@ -71,16 +71,12 @@
         otv_Coverage_validate( Coverage, valid, -1 );
 
         idx = otv_Coverage_get_first( Coverage ) + DeltaGlyphID;
-        if ( idx < 0 ||
-	    idx + DeltaGlyphID < 0 ||
-	    (FT_UInt)idx + DeltaGlyphID >= valid->glyph_count )
-          FT_INVALID_GLYPH_ID;
+        if ( idx < 0 )
+          FT_INVALID_DATA;
 
         idx = otv_Coverage_get_last( Coverage ) + DeltaGlyphID;
-        if ( (FT_UInt)idx >= valid->glyph_count ||
-	    idx + DeltaGlyphID < 0 ||
-	    (FT_UInt)idx + DeltaGlyphID >= valid->glyph_count )
-          FT_INVALID_GLYPH_ID;
+        if ( (FT_UInt)idx >= valid->glyph_count )
+          FT_INVALID_DATA;
       }
       break;