"client-error-not-possible" when trying to print to a file

[Alex]

Keep getting stuck with "client-error-not-possible" whenever I try to create a printer (page_warn) that prints to a file (/tmp/page_warn)  I've tried different names and doing it through 3 different methods (Webmin, Terminal, CUPS WWW config tool.)  I went to the manual, found the conf setting for being able to write to files and set it to Yes to no avail.  I'm running the default CUPS on Mandrake 10.  Any help would be appreciated.