Adding an argument to Sleeping signal

[Phillip Susi]

On 3/8/2011 6:43 AM, Richard Hughes wrote:
> On 7 March 2011 20:54, Phillip Susi <psusi at cfl.rr.com> wrote:
>> Could an argument about whether we are suspending or hibernating be
>> added to org.freedesktop.UPower.Sleeping?
> 
> That's probably a sane request, although it would break API.

Is there a way to do it without breaking the API?  Perhaps by defining a
2.0 interface rev that has the argument?