Trouble with Nist Net

I've got Nist Net set up on a Linux (Red Hat 9) box with two machines
connected to it. I'm using the X interface. Here's the weirdness:
If I put in a delay, a delay sigma or a packet drop percentage,
everything works exactly as it should. If I specify a bandwidth
limitation other than 0, even a ridiculously high one, packet traffic
stops dead. It's almost like the polarity on that field is reversed:
0 means no limitation, non-zero means infinite limitation.

The Nist Net documentation is pretty skimpy. Am I doing something
wrong here? Am I supposed to be doing something other than punching
in a number in the bandwidth field for the number of bytes per second
I want to get through?

Thanks for any help!

-- Rich Fife --