Yes, you need to login to your BIS and click edit next to the account you want to make changes to (Yahoo in this case). There you can edit your password. Don't forget to hit save when you're done.
This doesn't work for me. I am not able to register on the BIS. Put my PIN and IMEI and it says that my phone isn't registered with my carrier (AT&T). Any other way to change my Yahoo password?
Edit:
FIXED, I realized that I have a new Blackberry whose PIN is not yet registered with BIS. Besides, the link above is for Verizon - change the ending from vzw to mycingular to get to AT&T.
i have tried the above method but its not working for me, i changed my password on yahoo. i did register on my phone in applications as said and i received a message saying a registered with my network.
The prob now is i cant login into the BIS link u sent.
pls help.