diff --git a/scheme/ikarus.io.ss b/scheme/ikarus.io.ss
index 4b5490d..5b782c6 100644
--- a/scheme/ikarus.io.ss
+++ b/scheme/ikarus.io.ss
@@ -761,7 +761,7 @@
         (let ([n (read! str 0 (string-length str))])
           (unless (fixnum? n) 
             (error who "invalid return value from read!" n))
-          (unless (<= 0 n (fxsub1 (string-length str)))
+          (unless (<= 0 n (string-length str))
             (error who "return value from read! is out of range" n))
           ($set-port-index! p 0) 
           ($set-port-size! p n)
@@ -811,7 +811,7 @@
         (let ([n (read! str 0 (string-length str))])
           (unless (fixnum? n) 
             (error who "invalid return value from read!" n))
-          (unless (<= 0 n (fxsub1 (string-length str)))
+          (unless (<= 0 n (string-length str))
             (error who "return value from read! is out of range" n))
           ($set-port-size! p n)
           (cond
diff --git a/scheme/last-revision b/scheme/last-revision
index b053645..de0cde0 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1205
+1207
diff --git a/scheme/tests.libraries.ss b/scheme/tests.libraries.ss
deleted file mode 100644
index c470dd9..0000000
--- a/scheme/tests.libraries.ss
+++ /dev/null
@@ -1,53 +0,0 @@
-
-
-(library (F)
-  (export f)
-  (import (ikarus))
-  (define f
-    (lambda (x) 12))
-  (printf "F invoked\n"))
-
-(library (G)
-  (export)
-  (import (ikarus) (F))
-  (define-syntax t f)
-  (printf "G invoked: f=~s\n" t))
-    
-(library (Q)
-  (export foo)
-  (import (ikarus))
-  (define-record foo (bar baz)))
-
-(library (R)
-  (export)
-  (import (ikarus) (Q))
-  (printf "RTD=~s\n" (type-descriptor foo)))
-
-(invoke (R))
-
-(library (F0)
-  (export f)
-  (import (ikarus))
-  (define g 17)
-  (define-syntax f
-    (lambda (x) #'h))
-  (define-syntax h 
-    (lambda (x) #'g))
-  (printf "F0 invoked\n"))
-
-;(library (F0 client)
-;  (export)
-;  (import (ikarus) (F0))
-;  (unless (= (f) 17) 
-;    (error #f "F0 client"))
-;  (printf "F0 client ok\n"))
-
-
-(library (F0 client)
-  (export)
-  (import (ikarus) (F0))
-  (f))
-
-(invoke (F0 client))
-
-
diff --git a/scheme/tests/bignums.ss b/scheme/tests/bignums.ss
index c77f0d1..167b532 100644
--- a/scheme/tests/bignums.ss
+++ b/scheme/tests/bignums.ss
@@ -7,7 +7,7 @@
       (define (test1 x prefix radix)
         (let ([s (string-append prefix 
                    (number->string x radix))])
-          (assert (equal? x (read (open-input-string s))))))
+          (assert (equal? x (read (open-string-input-port s))))))
       (test1 x "#x" 16)
       (test1 x "#o" 8)
       (test1 x "#b" 2))
diff --git a/scheme/tests/input-ports.ss b/scheme/tests/input-ports.ss
index 7a3d85e..f2c5b4e 100644
--- a/scheme/tests/input-ports.ss
+++ b/scheme/tests/input-ports.ss
@@ -6,11 +6,11 @@
 
   (define-tests test-input-ports
     [eof-object?
-     (get-line (open-input-string ""))]
+     (get-line (open-string-input-port ""))]
     [(lambda (x) (equal? x "abcd"))
-     (get-line (open-input-string "abcd"))]
+     (get-line (open-string-input-port "abcd"))]
     [(lambda (x) (equal? x ""))
-     (get-line (open-input-string "\nabcd"))]
+     (get-line (open-string-input-port "\nabcd"))]
     [(lambda (x) (equal? x "abcd"))
-     (get-line (open-input-string "abcd\nefg"))]))
+     (get-line (open-string-input-port "abcd\nefg"))]))
 
diff --git a/scheme/tests/reader.ss b/scheme/tests/reader.ss
index 0820f75..6f76565 100644
--- a/scheme/tests/reader.ss
+++ b/scheme/tests/reader.ss
@@ -6,7 +6,7 @@
     (lambda (str)
       (lambda (n?)
         (and (number? n?)
-             (= (with-input-from-string str read) n?)))))
+             (= (read (open-string-input-port str)) n?)))))
 
   (define-syntax reader-tests
     (syntax-rules ()
@@ -75,29 +75,29 @@
   
   (define-tests test-char-syntax
     [(lambda (x) (= (char->integer x) #x0)) 
-     (read (open-input-string "#\\nul"))]
+     (read (open-string-input-port "#\\nul"))]
     [(lambda (x) (= (char->integer x) #x7)) 
-     (read (open-input-string "#\\alarm"))]
+     (read (open-string-input-port "#\\alarm"))]
     [(lambda (x) (= (char->integer x) #x8)) 
-     (read (open-input-string "#\\backspace"))]
+     (read (open-string-input-port "#\\backspace"))]
     [(lambda (x) (= (char->integer x) #x9)) 
-     (read (open-input-string "#\\tab"))]
+     (read (open-string-input-port "#\\tab"))]
     [(lambda (x) (= (char->integer x) #xA)) 
-     (read (open-input-string "#\\linefeed"))]
+     (read (open-string-input-port "#\\linefeed"))]
     [(lambda (x) (= (char->integer x) #xA)) 
-     (read (open-input-string "#\\newline"))]
+     (read (open-string-input-port "#\\newline"))]
     [(lambda (x) (= (char->integer x) #xB)) 
-     (read (open-input-string "#\\vtab"))]
+     (read (open-string-input-port "#\\vtab"))]
     [(lambda (x) (= (char->integer x) #xC)) 
-     (read (open-input-string "#\\page"))]
+     (read (open-string-input-port "#\\page"))]
     [(lambda (x) (= (char->integer x) #xD)) 
-     (read (open-input-string "#\\return"))]
+     (read (open-string-input-port "#\\return"))]
     [(lambda (x) (= (char->integer x) #x1B)) 
-     (read (open-input-string "#\\esc"))]
+     (read (open-string-input-port "#\\esc"))]
     [(lambda (x) (= (char->integer x) #x20)) 
-     (read (open-input-string "#\\space"))]
+     (read (open-string-input-port "#\\space"))]
     [(lambda (x) (= (char->integer x) #x7F)) 
-     (read (open-input-string "#\\delete"))])
+     (read (open-string-input-port "#\\delete"))])
 
   )