[racket] Custom syntax colorer in DrRacket's REPL?

Hello,

I am developing a custom non-sexp language in Racket.
Here is how I provide my own syntax colorer for it
in module mylang/lang/reader.rkt:

#:info (lambda (key defval default)
           (case key
             [(color-lexer)
              (dynamic-require 'mylang/tool/syntax-color
                               'get-syntax-token)]
             [else (default key defval)]))

It works great in DrRacket's definitions window, but does
not work in the interactions window -- the standard syntax
coloring is used there. Does anybody know how to fix that?

Best regards,

Dmitry