diff --git a/collects/scheme/private/contract.ss b/collects/scheme/private/contract.ss
index c1ba0f5c48..1061e62ba6 100644
--- a/collects/scheme/private/contract.ss
+++ b/collects/scheme/private/contract.ss
@@ -1463,6 +1463,7 @@ improve method arity mismatch contract violation error messages?
    (λ (x)
      (and (number? x)
           (integer? x)
+          (exact? x)
           (x . >= . 0)))))
 
 (define (integer-in start end)
diff --git a/collects/tests/mzscheme/contract-test.ss b/collects/tests/mzscheme/contract-test.ss
index 22f9a040be..52ef6ffe3f 100644
--- a/collects/tests/mzscheme/contract-test.ss
+++ b/collects/tests/mzscheme/contract-test.ss
@@ -4534,6 +4534,7 @@ so that propagation occurs.
   (test-flat-contract '(real-in 1 10) 3/2 20)
   (test-flat-contract '(string-len/c 3) "ab" "abc")
   (test-flat-contract 'natural-number/c 5 -1)
+  (test-flat-contract 'natural-number/c #e3 #i3.0)
   (test-flat-contract 'false/c #f #t)
   
   (test-flat-contract #t #t "x")