diff --git a/collects/tests/typed-scheme/succeed/list-struct-sum.ss b/collects/tests/typed-scheme/succeed/list-struct-sum.ss
index 08e7d49f..d448eac8 100644
--- a/collects/tests/typed-scheme/succeed/list-struct-sum.ss
+++ b/collects/tests/typed-scheme/succeed/list-struct-sum.ss
@@ -13,4 +13,13 @@
    [else (+ (Cons-first alon)
             (sum (Cons-rest alon)))]))
 
-(sum (make-Cons 5 (make-Cons 3 (make-Cons 1 (make-Empty)))))
\ No newline at end of file
+
+(: sum2 ((ListOf Number) -> Number))
+(define (sum2 alon)
+ (cond
+   [(Empty? alon) 0]
+   [(Cons? alon) (+ (Cons-first alon)
+                    (sum2 (Cons-rest alon)))]))
+
+(sum (make-Cons 5 (make-Cons 3 (make-Cons 1 (make-Empty)))))
+(sum2 (make-Cons 5 (make-Cons 3 (make-Cons 1 (make-Empty)))))
\ No newline at end of file
diff --git a/collects/typed-scheme/typecheck/tc-structs.ss b/collects/typed-scheme/typecheck/tc-structs.ss
index 207e34d7..e48ff90b 100644
--- a/collects/typed-scheme/typecheck/tc-structs.ss
+++ b/collects/typed-scheme/typecheck/tc-structs.ss
@@ -87,6 +87,7 @@
 (define (mk/register-sty nm flds parent parent-field-types types 
                          #:wrapper [wrapper values] 
                          #:type-wrapper [type-wrapper values]
+                         #:pred-wrapper [pred-wrapper values]
                          #:mutable [setters? #f]
                          #:proc-ty [proc-ty #f]
                          #:maker [maker* #f]
@@ -105,6 +106,7 @@
         (register-struct-types nm sty flds external-fld-types external-fld-types/no-parent setters? 
                                #:wrapper wrapper
                                #:type-wrapper type-wrapper
+                               #:pred-wrapper pred-wrapper
                                #:maker (or maker* maker)
                                #:constructor-return cret))))
 
@@ -114,6 +116,7 @@
 (define (register-struct-types nm sty flds external-fld-types external-fld-types/no-parent setters?
                                #:wrapper [wrapper values]
                                #:type-wrapper [type-wrapper values]
+                               #:pred-wrapper [pred-wrapper values]
                                #:maker [maker* #f]
                                #:constructor-return [cret #f])
   ;; create the approriate names that define-struct will bind
@@ -126,7 +129,7 @@
      (list (cons (or maker* maker) 
                  (wrapper (->* external-fld-types (if cret cret name))))
            (cons pred
-                 (make-pred-ty (wrapper name))))
+                 (make-pred-ty (pred-wrapper name))))
      (map (lambda (g t) (cons g (wrapper (->* (list name) t)))) getters external-fld-types/no-parent)
      (if setters?
          (map (lambda (g t) (cons g (wrapper (->* (list name t) -Void)))) setters external-fld-types/no-parent)
@@ -168,6 +171,7 @@
                    ;; wrap everything in the approriate forall
                    #:wrapper (lambda (t) (make-Poly tvars t))
                    #:type-wrapper (lambda (t) (make-App t new-tvars #f))
+                   #:pred-wrapper (lambda (t) (subst-all (for/list ([t tvars]) (list t Univ)) t))
                    #:poly? #t))