ethereal set up problem

[suman]

hi ,
I searched ethereal in my fedora core 4. i used "rpm -q ethereal". First 
time it does not show anything. After that i installed update from  
redhat site
now it shows
suman]$ rpm -q ethereal
ethereal-0.10.13-1.FC4.2
suman]$ rpm -q ethereal
ethereal-0.10.13-1.FC4.2
but when i issue ethereal -h .....nothing is comming it shows bad 
password...please help me how to run ethereal properly.