diff --git a/collects/parser-tools/lex-sre.ss b/collects/parser-tools/lex-sre.ss
index 84f7aa0..00d495b 100644
--- a/collects/parser-tools/lex-sre.ss
+++ b/collects/parser-tools/lex-sre.ss
@@ -70,7 +70,7 @@
   (define-lex-trans ~
     (syntax-rules ()
       ((_ re ...)
-       (complement (union re ...)))))
+       (char-complement (union re ...)))))
   
   (define-lex-trans (sre-- stx)
     (syntax-case stx ()