Solaris to Linux CUPS Print Conversion

[Dervish]

We have a Solaris server that overlays a "test data" image on top of all files sent to the jetDirect printers.  I have copied the script over to the Linux server that takes care of this process, but do not know how to integrate it into CUPS.  The script can be run by typing vtklp -dprinter -o option file-to-print.  It will then overlay the test image onto the file to be printed and send it to the destination printer.  How can I integrate this into the CUPS system?  I've tried lpadmin -d printer -i path-to-vtklp but that just caused the print job to hang.  Any help would be greatly appreciated.  Thanks.