printerproblem HP descjet 5740

[ph.walderdorff at aon.at]

When I try to modify my Printer via CUPS www administrations tool
Configure printer

the error comes:
server-error-service-unavailable

I can print, but printing is not very fine. As I could not find
descjet 5740 I have chosen another similer driver.

I downloaded
hp5500c1.ppd               and
HP-Descjet_5740-hpijs.ppd

Then I tried to find a way to integrate one of these files into CUPS
but I could not manage it because of the error above.

Does anyone know: why I cannot modify my printer and
                  where to put the adress of    				   HHP-Descjet_5740-hpijs.ppd
I suppose in /etc/printcap  ??
But how ?
certenly there is a menudroven way in CUPS.

Thanks Philipp