The Following Story appeared on AllBoutN9:
Several users asked how it's possible to install and use moreinstant messaging clients on Nokia N9. An application calledExtraplugins exactly does that - Nokia banned this plug-in from their store without any comprehensible reason.
About Extraplugins and how to install them
Extraplugins by coderus adds more services to Accounts. This way the user gets access to ICQ, Windows Live Messenger, Jabber, Odnoklassniki, QIP, Vkontakte and Yahoo!
No additional messenger application is needed - Extraplugin uses the integrated messaging services of the N9. This means all added accounts can be used like Skypeor Gtalk. Contacts from those clients are merged with phone Contacts after first log-in.
The flawless system-integration of instant messaging is amazing. Although it can be that your list of phone contacts gets incredibly long. Sending media files isn't supported.
Extraplugins used to be available in Nokia store but unfortunately got deleted recently. The official reason Nokia gave is rather ridiculous (source). So don't worry to install this application, it works very well and has a lot of happy users. Nevertheless there are some important steps you need to follow to make Extraplugins work the right way.
For the Instructions please visit AllBoutN9