Comment 11 for bug 269504

I've tested your new human-icon-theme package, but it still does show a black rectangle.
After some investigation I've found out the following:

The icon for the suspend-action at the moment needs to be called "sleep", take e.g. a look at
80_new_upstream_session_dialog.patch from gnome-session sources:

Here is the relevant part (gnome-session-2.24.0/gnome-session/gsm-logout-dialog.c)

+#define GSM_ICON_LOGOUT "system-log-out"
+#define GSM_ICON_SWITCH "system-users"
+#define GSM_ICON_SHUTDOWN "system-shutdown"
+#define GSM_ICON_REBOOT "view-refresh"
+/* TODO: use gpm icons? */
+#define GSM_ICON_HIBERNATE "drive-harddisk"
+#define GSM_ICON_SLEEP "sleep"

As you can see, the naming scheme is far from beeing ideal. Maybe a bug against gnome-session should be filed to use sane icon-names for this kind of actions (and which are included in gnome/tango/human themes).