diff --git a/src/ikarus.boot b/src/ikarus.boot
index ae08c7c..b6f735f 100644
Binary files a/src/ikarus.boot and b/src/ikarus.boot differ
diff --git a/src/ikarus.numerics.ss b/src/ikarus.numerics.ss
index 1024f15..206fd23 100644
--- a/src/ikarus.numerics.ss
+++ b/src/ikarus.numerics.ss
@@ -8,12 +8,13 @@
 (library (ikarus flonums)
   (export $flonum->exact $flonum-signed-biased-exponent flonum-parts
           inexact->exact exact $flonum-rational? $flonum-integer? $flzero?
-          $flnegative? flpositive? flabs)
+          $flnegative? flpositive? flabs fixnum->flonum)
   (import 
     (ikarus system $bytevectors)
     (except (ikarus system $flonums) $flonum-signed-biased-exponent
             $flonum-rational? $flonum-integer?)
-    (except (ikarus) inexact->exact exact flpositive? flabs))
+    (except (ikarus) inexact->exact exact flpositive? flabs
+            fixnum->flonum))
   
   (define (flonum-bytes f)
     (unless (flonum? f) 
@@ -130,6 +131,12 @@
             ($fl* x -1.0)
             x)
         (error 'flabs "~s is not a flonum" x)))
+
+  (define (fixnum->flonum x)
+    (if (fixnum? x) 
+        ($fixnum->flonum x)
+        (error 'fixnum->flonum "~s is not a fixnum")))
+
   )
 
 
diff --git a/src/makefile.ss b/src/makefile.ss
index c9d5607..2bcb01c 100755
--- a/src/makefile.ss
+++ b/src/makefile.ss
@@ -492,6 +492,7 @@
     [exact-integer-sqrt      i r]
     [exact->inexact          i r]
     [inexact->exact          i r]
+    [fixnum->flonum          i r]
     [exact                   i r]
     [inexact                 i r]
     [random                  i]
diff --git a/src/todo-r6rs.ss b/src/todo-r6rs.ss
index 76e8398..50a3d5f 100755
--- a/src/todo-r6rs.ss
+++ b/src/todo-r6rs.ss
@@ -298,7 +298,7 @@
     [fxxor                                      D fx]
     [fxzero?                                    D fx]
     ;;;
-    [fixnum->flonum                             S fl]
+    [fixnum->flonum                             C fl]
     [fl*                                        C fl]
     [fl+                                        C fl]
     [fl-                                        C fl]