diff --git a/scheme/ikarus.reader.ss b/scheme/ikarus.reader.ss
index 0f5f6a0..34c2c0d 100644
--- a/scheme/ikarus.reader.ss
+++ b/scheme/ikarus.reader.ss
@@ -90,25 +90,23 @@
     (lambda (c)
       (or (and ($char<= #\a c) ($char<= c #\z))
           (and ($char<= #\A c) ($char<= c #\Z)))))
-  (define af? 
-    (lambda (c)
-      (or (and ($char<= #\a c) ($char<= c #\f))
-          (and ($char<= #\A c) ($char<= c #\F)))))
-  (define af->num
-    (lambda (c)
-      (if (and ($char<= #\a c) ($char<= c #\f))
-          (fx+ 10 (fx- ($char->fixnum c) ($char->fixnum #\a)))
-          (fx+ 10 (fx- ($char->fixnum c) ($char->fixnum #\A))))))
   (define special-initial?
     (lambda (c)
       (memq c '(#\! #\$ #\% #\& #\* #\/ #\: #\< #\= #\> #\? #\^ #\_ #\~))))
-  (define subsequent?
-    (lambda (c)
-      (or (initial? c) (digit? c) (special-subsequent? c)
-          (memq (char-general-category c) '(Nd Mc Me)))))
   (define special-subsequent?
     (lambda (c)
       (memq c '(#\+ #\- #\. #\@))))
+  (define subsequent?
+    (lambda (c)
+      (cond
+        [($char<= c ($fixnum->char 127))
+         (or (letter? c)
+             (digit? c)
+             (special-initial? c) 
+             (special-subsequent? c))]
+        [else 
+          (or (unicode-printable-char? c)
+              (memq (char-general-category c) '(Nd Mc Me)))])))
   (define tokenize-identifier
     (lambda (ls p)
       (let ([c (peek-char p)])
diff --git a/scheme/last-revision b/scheme/last-revision
index 3603fbf..6fcfa77 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1573
+1574
diff --git a/scheme/pass-specify-rep-primops.ss b/scheme/pass-specify-rep-primops.ss
index 44b1b2a..876e952 100644
--- a/scheme/pass-specify-rep-primops.ss
+++ b/scheme/pass-specify-rep-primops.ss
@@ -1560,7 +1560,9 @@
               (let f ([i i]) 
                 (cond
                   [(zero? i) x]
-                  [else (prm 'sll/overflow (f (- i 1)) (K 1))]))]
+                  [else
+                   (interrupt)
+                   (prm 'sll/overflow (f (- i 1)) (K 1))]))]
              [else 
               (with-tmp ([x2 (prm 'sll x (K i))])
                 (interrupt-unless (prm '= (prm 'sra x2 (K i)) x))