I am using pidgin as chat client for both yahoo and gtalk. Recently, yahoo has stopped support for older versions of their own yahoo messenger clients. ( anything less than version 7.5 fails ) . It also means that most of the third party clients such as pidgin has problems in login.
On my ubuntu 9.04, the default pidgin version is 2.5.5. You can work around the yahoo login problem as shown below.
Open Accounts-> Manage accounts.
Click on the account you want to fix
Click on modify.
Click on advanced tab.
The pager server is set to scs.msg.yahoo.com
Change it to cs101.msg.mud.yahoo.com
Click on Save
It seems yahoo is rolling out a new authentication protocol. Let us wait for a new pidgin update
Pidgin 2.5.7 which fixes the yahoo login problem is out. You can install it as given below.
Import the public key for Launchpad PPA for Pidgin Developers
$ sudo apt-key adv –recv-keys –keyserver keyserver.ubuntu.com \ 67265eb522bdd6b1c69e66ed7fb8bee0a1f196a8
Add the following lines to /etc/apt/sources.list
deb http://ppa.launchpad.net/pidgin-developers/ppa/ubuntu jaunty main
Run apt-get update and apt-get install pidgin.
The PPA contains new pidgin releases for other versions of ubuntu ( dapper gutsy, hardy ,intrepid and karmic) You can just replace jaunty in sources.list line indicating this ppa with you distro and enjoy yahoo messenger on pidgin.