[ic] Need help with runtime error --- UPS shipping

[interchange-users@interchange.redhat.com (Wu-Sun Cheng)]

Hi, I am a new user of interchange. Rencently I downloaded interchange4.8.3
and installed the demo "foundation".
While playing with the demo I got a runtime error everytime I tried to do
"checkout" as shown in the following:

9.37.223.169 Y37YqLhP:9.37.223.169 - [19/April/2002:16:15:37 -0400]
foundation/cgi-bin/foundation/process.html Runtime error: Undefined
subroutine &Vend::Interpolate::getUPS called at (eval 114) line 17.

I tthought I had everything installed properly followed the instruction and
don't know why I still got this error.
Any suggestions/comments are welcome. Thanks!

Regards, Wu-Sun