Conky and ARGB transparency

Hi,

I have a problem with conky argb transparency, this my conkyrc: 

background yes 
use_xft yes
xftfont Terminus:size=8
xftalpha 1
update_interval 2.0
total_run_times 0

#------interesting part
own_window yes
own_window_transparent yes
own_window_argb_visual yes
own_window_type desktop
own_window_class conky-semi
own_window_hints undecorated,below,sticky,skip_taskbar,skip_pager
#-----

double_buffer yes
draw_shades no 
draw_outline no
draw_borders no
stippled_borders 8
border_margin 4
border_width 1
default_color white
default_shade_color black
default_outline_color white
alignment bottom_left
gap_x 10
gap_y 10
no_buffers yes
uppercase no
cpu_avg_samples 2
net_avg_samples 2
override_utf8_locale no
use_spacer yes

I've already followed the instructions in http://fluxbox-wiki.org/index.php/Transparency to enable xcompmgr and transset-df 
seems to work (even if when I move the window the opacity is still reset to 100%).

Any Idea???

Thanks

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