Comment 7 for bug 637405

I don't think this is evince releated...

Also if you, when adding the printer in system-config-printer -> Add -> Network printer -> Windows Printer via Samba, choose "Set authentication details now" instead of "Promt user if authentication is required", your password will be remembered... And if you're login details are wrong it will offer you the option of saving them...

So it seems that the "Promt user if authentication is required" never allows the user to save the login credentials, this is inconsistent and doesn't really make sense... This is probably a bug in the part of gnome that manages printer authentication...