In TeX Live we treat all output files as binary.

diff -ur t1utils-1.37.orig/t1ascii.c t1utils-1.37/t1ascii.c
--- t1utils-1.37.orig/t1ascii.c	2011-04-04 16:47:49.000000000 +0200
+++ t1utils-1.37/t1ascii.c	2012-08-12 13:07:47.000000000 +0200
@@ -281,6 +281,7 @@
   /* As we are processing a PFB (binary) input */
   /* file, we must set its file mode to binary. */
   _setmode(_fileno(ifp), _O_BINARY);
+  _setmode(_fileno(ofp), _O_BINARY);
 #endif
 
   /* prepare font reader */
diff -ur t1utils-1.37.orig/t1disasm.c t1utils-1.37/t1disasm.c
--- t1utils-1.37.orig/t1disasm.c	2011-07-20 18:22:17.000000000 +0200
+++ t1utils-1.37/t1disasm.c	2012-08-12 13:08:15.000000000 +0200
@@ -747,6 +747,7 @@
   /* As we might be processing a PFB (binary) input file, we must set its file
      mode to binary. */
   _setmode(_fileno(ifp), _O_BINARY);
+  _setmode(_fileno(ofp), _O_BINARY);
 #endif
 
   /* prepare font reader */
diff -ur t1utils-1.37.orig/t1unmac.c t1utils-1.37/t1unmac.c
--- t1utils-1.37.orig/t1unmac.c	2011-04-04 16:47:49.000000000 +0200
+++ t1utils-1.37/t1unmac.c	2012-08-12 13:23:32.000000000 +0200
@@ -651,8 +651,7 @@
   _setmode(_fileno(ifp), _O_BINARY);
   /* If we are processing a PFB (binary) output */
   /* file, we must set its file mode to binary. */
-  if (pfb)
-    _setmode(_fileno(ofp), _O_BINARY);
+  _setmode(_fileno(ofp), _O_BINARY);
 #endif
 
   if (pfb)