Might be a regional thing...meaning it's available in some countries and in others it isn't. On mine it does have filesharing but not the calendar sharing.
Alternately you can use Plus! File Sharing
From
Changelog:
The file sharing feature of Messenger Plus! was not that useful as is so it has been redesigned and file triggers have been added to it:
For each file entry you can set a different trigger (IRC like). A trigger is a message preceded by ! that, when sent by a contact, will automatically send the specified file on your behalf.
File triggers can have many uses. For example, if you just had found and downloaded a great program/music/video, you could advertise a trigger for it in your personal message.
An option (off by default) allows contacts to send a !listfiles trigger to get the list of every file you are currently sharing with triggers.
A simple flood protection is enforced by Messenger Plus! rejecting new requests that are sent too quickly.
I know some of you will request a password for this feature but in a way, they are already implicitly supported: a trigger can have up to 100 characters and can include spaces. So if you create a trigger "!myfile thepassword" you can advertise for it as "!myfile <add password here>".
For security reasons, file triggers do not work in chats with multiple contacts.
A /fileshare command has been added to access the file sharing panel.
Remember that Messenger is not a software designed for mass automatic file sharing. Messenger Plus! does not bypass any of the native protections of Messenger which means for example that if you are using Messenger 7, some file extensions will be forbidden (you can use the StuffPlug plugin or Windows Messenger to avoid that problem). Also, please remember that Messenger automatically limits the number of simultaneous file transfers, Messenger Plus! cannot do anything about it either.
Currently, up to 12 different files can be shared through this method.
You can reach this option by clicking the Plus! icon in the type in field or by typing /fileshare. Ofcourse your contact will need MsgPlus! aswell to be able to "browse" the files you share.
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