You can login with multiple ID's on the same yahoo messenger.
Follow these steps : ==>>
* Go to Start ==> Run ==>> Type regedit,hit enter
* Go to HKEY_CURRENT_USER ==>> Software ==>> Yahoo ==>> pager ==>>Test
* On the right pane ==>> right-click and choose new Dword value .
* Rename it as Plural.
* Double click and assign a decimal value of 1.
* Now close registry and restart yahoo messenger.
* For signing in with new id open another messenger .
