diff --git a/scheme/ikarus.bytevectors.ss b/scheme/ikarus.bytevectors.ss
index 47eff3d..7b2ad3f 100644
--- a/scheme/ikarus.bytevectors.ss
+++ b/scheme/ikarus.bytevectors.ss
@@ -750,7 +750,7 @@
                    ($fx< i0 bvsize))
         (die who "invalid index" i0))
       (unless (and (fixnum? size) 
-                   ($fx>= size 0) 
+                   ($fx> size 0)
                    ($fx<= i0 ($fx- bvsize size)))
         (die who "invalid size" size)))
     (let ([nsize (bitwise-length n)])
@@ -788,7 +788,7 @@
                    ($fx< i0 bvsize))
         (die who "invalid index" i0))
       (unless (and (fixnum? size) 
-                   ($fx>= size 0) 
+                   ($fx> size 0) 
                    ($fx<= i0 ($fx- bvsize size)))
         (die who "invalid size" size)))
     (let ([nsize (+ (bitwise-length n) 1)])
diff --git a/scheme/last-revision b/scheme/last-revision
index bddb3cd..d42f634 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1844
+1845