diff --git a/scheme/ikarus.fixnums.ss b/scheme/ikarus.fixnums.ss
index 8206d7c..2271e4e 100644
--- a/scheme/ikarus.fixnums.ss
+++ b/scheme/ikarus.fixnums.ss
@@ -386,7 +386,7 @@
     (define $fixnum->string
       (lambda (x radix)
         (cond
-          [($fxzero? x) "0"]
+          [($fxzero? x) (string #\0)]
           [($fx> x 0)
            (call-with-values
              (lambda () (f x 0 0 radix))
diff --git a/scheme/last-revision b/scheme/last-revision
index 4ab81d9..70bdf7b 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1296
+1297