VSP API returning same image and ignoring "prinatable" variable

Hello all,

Today I have noticed that Variable Star Plotter API is returning same image and completly ingnoring "printable" parameter.

Example request:

http://www.aavso.org/cgi-bin/vsp.pl?name=ss+cyg&forcelines=on&fov=60&printable=no
http://www.aavso.org/cgi-bin/vsp.pl?name=ss+cyg&forcelines=on&fov=60&printable=yes

Those two request are returning same image of selected FOV, while first one should return 75dpi and second one 150dpi version of image. Also, sending request to:

http://www.aavso.org/vsp/chart?name=ss+cyg&forcelines=on&fov=60&printable=yes

Returns broken page. I guess that png image is injected into HTML and not returned for itself.

Regards,
Dario