diff --git a/src/psl-make-dafsa b/src/psl-make-dafsa
index 0d4408a..46f0406 100755
--- a/src/psl-make-dafsa
+++ b/src/psl-make-dafsa
@@ -519,10 +519,10 @@ def parse_psl2c(infile, utf_mode):
   for line in lines:
     if line[-3:-1] != ', ':
       raise InputError('Expected "domainname, <digit>", found "%s"' % line)
-    # Technically the DAFSA format could support return values in range [0-31],
+    # Technically the DAFSA format could support return values in range [0x00-0x1E],
     # but the values below are the only with a defined meaning.
     if line[-1] not in '0123456789ABCDEF':
-      raise InputError('Expected value to be one of {0,1,2,4,5}, found "%s"' % line[-1])
+      raise InputError('Expected value to be in range [0-9] or [A-F], found "%s"' % line[-1])
 
 #  with open("gperf.out", 'w') as outfile:
 #    for line in sorted(lines):