shell mode cursor movement snafu.

I am experiencing a problem in shell using XEmacs 21.2-b13 (and in 21.2-b9). When I am running a program that produces lots of output and I press page up or cursor up or page down or cursor down (etc...), the display freezes. The cursor movement will not display until *after* the program exits. If I break it (^C^C), the display will unfreeze when the break reaches the program. The break (^C^C) can take 10 or more seconds to take place and about 1000 more lines received in the buffer. Has anyone else experienced this? I search the mailing-list and found nothing on this. Please help, =============================== Rodney Stromlund Southwest Airlines Co. Systems Department Sales & Revenue Accounting Group mailto:rstromlu＠wnco.com (214) 792-6484 ===============================