[plt-scheme] Install PLAI package on PLTScheme

Hi folks,

I am using DrScheme on Ubuntu 8.10. While running the following two
lines:

#lang scheme
(require (planet plai/plai:1:1))

I got an error:
. . .plt-scheme/planet/300/4.0/cache/cce/scheme.plt/4/1/syntax.ss:
115:14: or/c: expected procedures of arity 1 or contracts, given: #f

Does anyone know how to resolve this?

Thanks,
Yan