diff --git a/pkgs/redex-pkgs/redex-lib/redex/private/reduction-semantics.rkt b/pkgs/redex-pkgs/redex-lib/redex/private/reduction-semantics.rkt
index 3e186fa01f..757adb9fe2 100644
--- a/pkgs/redex-pkgs/redex-lib/redex/private/reduction-semantics.rkt
+++ b/pkgs/redex-pkgs/redex-lib/redex/private/reduction-semantics.rkt
@@ -1870,7 +1870,7 @@
                            (syntax-case nt-def ()
                              [(x . whatever) #'x]))]
                         [bindings
-                         (record-nts-disappeared-bindings (syntax->list #'(nt-ids ...)))])
+                         (record-nts-disappeared-bindings #'lang-name (syntax->list #'(nt-ids ...)))])
            (quasisyntax/loc stx
              (begin
                bindings
@@ -1886,26 +1886,34 @@
                         (identifier? #'x)
                         #'define-language-name]))
                    '(all-names ...)
-                   (to-table #'(nt-ids ...)))))
+                   (to-table #'lang-name #'(nt-ids ...)))))
                (define define-language-name
                  #,(syntax/loc stx (language form-name lang-name (all-names ...) (names prods ...) ...))))))))]))
 
-(define-for-syntax (record-nts-disappeared-bindings nt-ids)
+(define-for-syntax (record-nts-disappeared-bindings lang nt-ids [prop `disappeared-binding])
   (let loop ([nt-ids nt-ids]
              [stx #'(void)])
     (cond
      [(null? nt-ids) stx]
      [else 
-      (define old (syntax-property stx 'disappeared-binding))
-      (define new (syntax-local-introduce (car nt-ids)))
+      (define old (syntax-property stx prop))
+      (define new (syntax-local-introduce (lang-nt-id lang (car nt-ids))))
       (loop (cdr nt-ids)
             (syntax-property stx
-                             'disappeared-binding
+                             prop
                              (if old (cons new old) new)))])))
 
-(define-for-syntax (to-table x)
+(define-for-syntax (lang-nt-id lang-stx nt-stx)
+  (format-id nt-stx "~a:~a" 
+             (syntax->datum lang-stx) 
+             (syntax->datum nt-stx)
+             #:source nt-stx
+             #:props nt-stx))
+             
+
+(define-for-syntax (to-table lang x)
   (for/hash ([id (in-list (syntax->list x))])
-    (values (syntax-e id) id)))
+    (values (syntax-e id) (lang-nt-id lang id))))
 
 (define-struct binds (source binds))
   
@@ -2005,10 +2013,13 @@
                          (for/list ([nt-def (in-list (syntax->list #'nt-defs))])
                            (syntax-case nt-def ()
                              [(x . whatever) #'x]))]
+                        [uses
+                         (record-nts-disappeared-bindings #'orig-lang (syntax->list #'(nt-ids ...)) 'disappeared-use)]
                         [bindings
-                         (record-nts-disappeared-bindings (syntax->list #'(nt-ids ...)))])
+                         (record-nts-disappeared-bindings #'name (syntax->list #'(nt-ids ...)))])
            (quasisyntax/loc stx
              (begin
+               uses
                bindings
                (define define-language-name 
                  #,(syntax/loc stx
@@ -2024,7 +2035,8 @@
                         (identifier? #'x)
                         #'define-language-name]))
                    '(all-names ...)
-                   (to-table #'(nt-ids ...))))))))))]))
+                   (to-table #'name #'(nt-ids ...))))))))))]))
+
 
 (define-syntax (extend-language stx)
   (syntax-case stx ()
diff --git a/pkgs/redex-pkgs/redex-lib/redex/private/term-fn.rkt b/pkgs/redex-pkgs/redex-lib/redex/private/term-fn.rkt
index 87c12cf2cf..c8514ae1cc 100644
--- a/pkgs/redex-pkgs/redex-lib/redex/private/term-fn.rkt
+++ b/pkgs/redex-pkgs/redex-lib/redex/private/term-fn.rkt
@@ -107,7 +107,9 @@
                             (syntax-position id-stx)
                             ;; shorten the span so it covers only up to the underscore
                             (string-length (symbol->string nt))))
-        (define the-id (datum->syntax table-entry nt the-srcloc id-stx))
+        (define the-id (datum->syntax table-entry
+                                      (syntax-e table-entry)
+                                      the-srcloc id-stx))
         (syntax-property the-id 'original-for-check-syntax #t)]
        [else
         #f])]
diff --git a/pkgs/redex-pkgs/redex-test/redex/tests/check-syntax-test.rkt b/pkgs/redex-pkgs/redex-test/redex/tests/check-syntax-test.rkt
index c2ff50467e..dcd0d1e02b 100644
--- a/pkgs/redex-pkgs/redex-test/redex/tests/check-syntax-test.rkt
+++ b/pkgs/redex-pkgs/redex-test/redex/tests/check-syntax-test.rkt
@@ -159,4 +159,49 @@
         (expected-arrows
          (list (list def-name use-name)))))
 
+;; extended language
+(let ([annotations (new collector%)])
+  (define-values (add-syntax done)
+    (make-traversal module-namespace #f))
+  
+  (define base-lang-def (identifier L1))
+  (define base-lang-use1 (identifier L1))
+  (define base-lang-use2 (identifier L1))
+  (define extended-lang-def (identifier L2))
+  (define extended-lang-use (identifier L2))
+  (define base-nt-name (identifier e))
+  (define base-nt-use (identifier e))
+  (define extended-nt-name (identifier e))
+  (define extended-nt-use (identifier e))
+  
+  (define base-lang-bindings
+    (list base-lang-def base-lang-use1 base-lang-use2))
+  (define extended-lang-bindings
+    (list extended-lang-def extended-lang-use))
+  (define base-nt-bindings
+    (list base-nt-name extended-nt-name base-nt-use))
+  (define extended-nt-bindings
+    (list extended-nt-name extended-nt-use))
+  
+  (parameterize ([current-annotations annotations]
+                 [current-namespace module-namespace])
+    (add-syntax
+     (expand #`(let ()
+                 (define-language #,base-lang-def
+                   (#,base-nt-name number))
+                 (define-extended-language #,extended-lang-def #,base-lang-use1
+                   (#,extended-nt-name .... variable))
+                 (redex-match #,base-lang-use2 #,base-nt-use 1)
+                 (redex-match #,extended-lang-use #,extended-nt-use 'x))))
+    (done))
+  
+  (test (send annotations collected-arrows)
+        (expected-arrows
+         (list base-lang-bindings
+               extended-lang-bindings
+               base-nt-bindings
+               extended-nt-bindings))))
+  
+    
+
 (print-tests-passed 'check-syntax-test.rkt)