[Sunhelp] set prompt not permanent

[beemern at telecom.ksu.edu]

For some reason... when I try to set my prompt.. it only works until i
use the 'cd' command again

example

68 /home/beemern % uname -a
SunOS caddo 5.7 Generic sun4u sparc SUNW,Ultra-1
69 /home/beemern % set prompt=%n@%m" ["%c"] "
beemern at caddo [~] cd
71 /home/beemern % 

the set prompt command will work/hold until i use the 'cd' command
once i do, it goes back to default prompt

any ideas?

Thanks
nathan