I am printing to a Canon PIXMA iP4500 printer using the CUPS driver of Gutenprint. The problem is, in the CUPS printer options dialog, the resolution setting has only two possible values: 600dpi and automatic. The output of lpoptions -l confirms that only these two options are available.
The printer supports resolutions up to 9600dpi so there should be more options. In addittion, this being an inkjet printer, the resolution changes the printing speed significantly.
I'm using Gutenprint v5.2.5 vanilla installed from source, and CUPS 1.3.8 of debian lenny package, the machine is x86_64 linux.
Thanks for your attention.