diff --git a/collects/typed-scheme/infer/constraints.ss b/collects/typed-scheme/infer/constraints.ss
index 08534ef4..54d0495d 100644
--- a/collects/typed-scheme/infer/constraints.ss
+++ b/collects/typed-scheme/infer/constraints.ss
@@ -4,7 +4,7 @@
 	 (types convenience utils union subtype)
 	 (rep type-rep)
 	 (utils tc-utils)
-	 unstable/sequence
+	 unstable/sequence unstable/hash
          "signatures.ss" "constraint-structs.ss"
          scheme/match)
 
diff --git a/collects/typed-scheme/infer/dmap.ss b/collects/typed-scheme/infer/dmap.ss
index 412482e3..1a3a9baa 100644
--- a/collects/typed-scheme/infer/dmap.ss
+++ b/collects/typed-scheme/infer/dmap.ss
@@ -3,8 +3,7 @@
 (require "../utils/utils.ss" 
 	 "signatures.ss" "constraint-structs.ss"
 	 (utils tc-utils)
-	 unstable/sequence
-         scheme/match)
+	 unstable/sequence unstable/hash scheme/match)
 
 (import constraints^)
 (export dmap^)
diff --git a/collects/typed-scheme/utils/utils.ss b/collects/typed-scheme/utils/utils.ss
index d2a24914..78a54952 100644
--- a/collects/typed-scheme/utils/utils.ss
+++ b/collects/typed-scheme/utils/utils.ss
@@ -6,13 +6,12 @@ at least theoretically.
 |#
 
 (require (for-syntax scheme/base syntax/parse scheme/string)
-         scheme/contract mzlib/plt-match scheme/require-syntax scheme/provide-syntax
-         mzlib/struct scheme/unit
-	 scheme/pretty mzlib/pconvert
-	 (except-in syntax/parse id))
+         scheme/contract scheme/match scheme/require-syntax 
+	 scheme/provide-syntax mzlib/struct scheme/unit
+	 scheme/pretty mzlib/pconvert syntax/parse)
 
 ;; to move to unstable
-(provide == hash-union debug reverse-begin)
+(provide == debug reverse-begin)
 
 (provide
  ;; timing
@@ -186,17 +185,6 @@ at least theoretically.
                #'([prop:custom-write pseudo-printer]))
          #f)]))
 
-;; map map (key val val -> val) -> map
-(define (hash-union h1 h2 f)
-  (for/fold ([h* h1])
-    ([(k v2) h2])
-    (let* ([v1 (hash-ref h1 k #f)]
-           [new-val (if v1
-                        (f k v1 v2)
-                        v2)])      
-    (hash-set h* k new-val))))
-
-
 
 ;; turn contracts on and off - off by default for performance.
 (define-for-syntax enable-contracts? #f)