Comment 12 for bug 335197

Next is the e-mail I sent to Tom Vetterlein, which contains some additional info regarding the bug:

You can find more info on the freedesktop notification specification, more specific in the following paragraph: http://www.galago-project.org/specs/notification/0.9/x408.html#command-get-capabilities
It seems that it's possible to call the GetCapabilities() method using DBus. Since it already sends the notification via DBus, this shouldn't be too hard.
GetCapabilities() will then return if 'actions' are supported. If this is the case, it is safe to include the buttons. Otherwise, they should be avoided. This can be done in the if-test I described in my previous comment.