Changing the artwork output dir

I want to write artworks to a design dependent output directory.

I have a script to create artworks,  

olddir = "output"
outdir = "output/123456-ND-A"
axlSetVariable("ads_sdart" outdir)  ; set working directory to output directory
 sprintf(script
 "scriptmode +i +n +w +c\n
 setwindow pcb\n
 artwork\n
 setwindow form.film_control\n
 FORM film_control select_all\n

 FORM film_control database_check YES\n
 FORM film_control create\n
 setwindow form.film_control\n
 FORM film_control ok\n
 setwindow pcb\n ")  ;end sprintf
 
 COD_replay_script(script)

 axlSetVariable("ads_sdart" olddir)  ;  

If I set "ads_sdart" using setup user preferences, it works fine. If I use this script, the artworks is generated in "output" and art_param.txt is generated in "output/123456-ND-A". That does not make any sense to me. Any surgestions?

Alternatively I could move the files afterwards, but that requires much more unessesary coding.