Can´t unparent an object

Hi, i need help with a parented object.
I´m currently doing a walking animation with a character that was not made by me but to move the feet manipulators i want to unparent them from the root manipulator so they could move independently from it.
I´ve tryed Alt+P and even Ctrl+Alt+C in case it was a constrain.
I´m adding a picture of the outliner with the manipulators in yellow so you can see how it is built.

http://img36.imageshack.us/img36/5097/helpv.jpg

So, any ideas?

Did you try deleting the “Parent” field in the Bone tab?


-rking

The parent field in the bone tab is greyed out, it shows “root” on it but i can´t modified it.
However there´s a Bone group field but it´s empty.

You gotta be in Edit Mode on the Armature. I should have mentioned that.

-rking

Ok, not very sure where we are going so here it is another pic
http://img52.imageshack.us/img52/139/helpii.jpg
I need to unparent those two little blue thingies around the feet from the big blue cross-shaped thingie on the floor.
I´ve been looking for an armature or anything called that way and couldn´t find it, is it possible it was renamed?
There´s an object called CharName_proxy that seems to move the entire character.