[plt-scheme] tex2page

Does anyone use tex2page to convert TeX strings to HTML strings?  I
would have expected the following to work, but it doesn't seem to.
Definitions window:

(module check (lib "plt-pretty-big.ss" "lang")
  (require (prefix t2p: (lib "tex2page-aux.ss" "tex2page")))
  )

Interactions window:

Welcome to DrScheme, version 4.2 [3m].
Language: Module; memory limit: 128 megabytes.
> (define t t2p:tex2page-string)
> (define t2 t2p:tex-string->html-string)
> (t "")
#t
> (t " ")
. . vector-ref: expects type <vector> as 1st argument, given: #f;
other arguments were: 2
> (t2 "")
""
> (t2 " ")
. . vector-ref: expects type <vector> as 1st argument, given: #f;
other arguments were: 2
>

Thanks,
Shriram