diff -urNad vdr-1.5.16~/font.c vdr-1.5.16/font.c
--- vdr-1.5.16~/font.c	2008-02-29 22:21:30.000000000 +0100
+++ vdr-1.5.16/font.c	2008-02-29 22:24:05.000000000 +0100
@@ -214,6 +214,9 @@
         return Glyph;
         }
      }
+#define UNKNOWN_GLYPH_INDICATOR '?'
+  if (CharCode != UNKNOWN_GLYPH_INDICATOR)
+     return Glyph(UNKNOWN_GLYPH_INDICATOR, AntiAliased);
   return NULL;
 }
 
@@ -258,6 +261,8 @@
            uint sym = Utf8CharGet(s, sl);
            s += sl;
            cGlyph *g = Glyph(sym, AntiAliased);
+           if (!g)
+              continue;
            int kerning = Kerning(g, prevSym);
            prevSym = sym;
            uchar *buffer = g->Bitmap();