[4.5] Sleep / hibernate not activated

[Luca Tettamanti <kronos.it@gmail.com>]

Hello,
I just downloaded the "experimental" KDE 4.5.1 packages and it seems
that somehow sleep/hibernate are broken (or rather KDE seems unable to
active them).
I can suspend just fine using s2ram/s2disk manually, but when I try
using Leave -> {Sleep, Hibernate} or the plasmoid nothing happens; no
obvious clues in .xsession-errors.
This BTW used to work with 4.4.
How is transition initiated by KDE? (using the helpers, via sysfs
interface, hal?) This might help me debug it further :)

Luca