diff --git a/implementations/racket/preserves/preserves-schema/bin/preserves-schema-rkt.rkt b/implementations/racket/preserves/preserves-schema/bin/preserves-schema-rkt.rkt
index 015f611..c3e9fe9 100644
--- a/implementations/racket/preserves/preserves-schema/bin/preserves-schema-rkt.rkt
+++ b/implementations/racket/preserves/preserves-schema/bin/preserves-schema-rkt.rkt
@@ -136,6 +136,8 @@
                      (error '--module "Argument must be Namespace=path: ~v" namespace=path))
                    (let* ((namespace-str (substring namespace=path 0 i))
                           (path-str (substring namespace=path (+ i 1))))
+                     (when (string-prefix? path-str ":")
+                       (set! path-str (string->symbol (substring path-str 1))))
                      (set! additional-modules
                            (cons (list (map string->symbol (string-split namespace-str "."))
                                        path-str)