diff --git a/scheme/ikarus.enumerations.ss b/scheme/ikarus.enumerations.ss
index 54c1347..f4ec7c6 100644
--- a/scheme/ikarus.enumerations.ss
+++ b/scheme/ikarus.enumerations.ss
@@ -18,7 +18,7 @@
     enum-set-constructor enum-set->list enum-set-member?
     enum-set-subset? enum-set=? enum-set-union enum-set-difference
     enum-set-intersection enum-set-complement enum-set-projection
-    make-file-options)
+    make-file-options enum-set?)
   (import 
     (except (ikarus)
       make-enumeration enum-set-universe enum-set-indexer
@@ -26,7 +26,7 @@
       enum-set-subset? enum-set=? enum-set-union enum-set-difference
       enum-set-intersection enum-set-complement
       enum-set-projection
-      make-file-options))
+      make-file-options enum-set?))
 
   (define-record-type enum-type
     (fields id mask symbol->index-hashtable index->symbol-vector)
diff --git a/scheme/last-revision b/scheme/last-revision
index d0f06a1..340b351 100644
--- a/scheme/last-revision
+++ b/scheme/last-revision
@@ -1 +1 @@
-1575
+1576
diff --git a/scheme/makefile.ss b/scheme/makefile.ss
index 973ffd6..ec8054a 100755
--- a/scheme/makefile.ss
+++ b/scheme/makefile.ss
@@ -1034,6 +1034,7 @@
     [enum-set-universe                           i r en]
     [enum-set=?                                  i r en]
     [make-enumeration                            i r en]
+    [enum-set?                                   i]
     [environment                                 i ev]
     [eval                                        i ev se]
     [raise                                       i r ex]