Expect and xterm

[Ishmael]

I would like to automate the following sequence:

1) Open xterm via Expect script.
2) Run a program in the new terminal.
3) 'Let go' of the new terminal, leaving it running (!).
4) Exit Expect script.

I can get as far as 1) with Perl's implementation of Expect, and as
far as 2) with TCL Expect (using the hocus pocus described in Don
Libes' book). Any ideas? (P.S. Using xterm's '-e' option won't work
in this case).
Thanks for your help!