Hi Sergio - Heavens Above had four daylight passes for Phobos-Grunt for Melbourne on Saturday, 10:56, 12:29, 17:13 and 18:47, so it doesn't look like your object was the misbehaving satellite. The last three were at low altitude in the sky, while the brightest of the four was mag 3.8 and none were visible passes.
http://www.heavens-above.com/
There's some pretty nasty stuff aboard and it looks like an uncontrolled re-entry will occur soon unless a miracle happens.
http://www.russianspaceweb.com/phobos_grunt_launch.html
http://news.discovery.com/space/russ...runt-lost.html
http://www.gizmag.com/phobos-grunt-t...n-orbit/20474/
"
If the Russians are unable to regain control, the Phobos-Grunt is expected to make an uncontrolled re-entry into the Earth's atmosphere, along with its 8.3 tons (7.5 tonnes) of highly toxic propellant and radioactive cobalt-57."
Cheers -