There are oodles of free PDF printer dirvers, which direct print output to a PDF file.  See these --

http://download.cnet.com/1770-20_4-0.html?query=Adobe+PDF+Printer+Driver+Plug+in&searchtype=downloads
http://download.cnet.com/PDF-Printer-Driver/3000-18497_4-10127664.html
www.thefreecountry.com/utilities/free-pdf-converters-drivers.shtml
www.primopdf.com/

You have to go through the oodles of programs to find the best at direct printer-to-PDF output, then setup your network to redirect the print jobs, and choose the PDF printer as the DEFAULT on that system.

Thank you , scrathcyboy.

I have viewed quite a number of these PDF printers, so far none of them support port 9100.  

This why I tried RawPrinterServer, as it could capture print job in 9100 port and send it to another printer (e.g. pdf printer). But just this RawPrinterServer seems not a fully function printer emulator, as the other pcs in the network won't see it as online printer.

I think you could load any of these printer drivers to port 9100 in windows.  Remember, the port assignment is a windows function (i.e. networking feature) and the app is on the other end and doesn't always know (i.e. doesn't need to know) where it gets the data from -- which is a windows function, and if the apps use the windows internet connect, they are oblivious to the path where they get the data from.

 I would look for the app that fills the need, and then wrestle with the port issue after you have found the right app.  As I see it, you biggest problem is not the data port, but the ability of the VMS to pass through whatever data you want via the port you want.  THere are limitations to the VMS OS in this regard.

It seems to me that a Windows printer sever is needed in this case, ideally something like hp jetdirect print server available inside HP printer.
So far haven't found any PDF printer acting as print server.

I just came across a product "ActiveFax Server", it did provide the Raw Server option to listen at 9100 port for document sent for fax.  I tested, it did work !
It capture the report printed from VMS system, reserve the original report layout. But I have to manually click on each pending fax queue to save it as PDF file.
So it is still that the idea solution that  raw print out can be captured and save into PDF automatically.

But it shed some light that there might be some PDFPrinter Server product meet the needs but yet to be found out.

A workstation computer + printer is the same as a stand-alone print server.  The port 9100 may be unique to this issue, and be the limiting factor.  Why 9100?  Why can't you change that to a standard printer port like LPT1?  If you could do that, the problem gets a whole lot simpler.  Why impose the 9100 limitation?  Seems to me the first step is to configure VMS to use a different port, like 3BC or 378.  Problem solved, as anything will work with printer ports 1 and 2, i.e. LPT1 and LPT2.

It is a proprietary system on VMS which is out of my control. as its reporting printing method apply to all departments.  If I can do that from that system end, I can just create one PDF printer and make it as shared network printer, and put it into print queue setting on VMS. All done. We just can't change it.

That is why I am struggling at the client site to get it solved.

The main purpose is to save the Earth.
As I want to save all reports in PDF for end-users to view and only print them when necessary. Currently all reports from that system are printed out overnight.

Thanks for your help anyway.

Port 9100 is a 'standard' printer destination port.  See this: http://support.microsoft.com/kb/246868 .  It is not however the source port.

Thank you DaveBaldwin.

That might be the solution, although I am a bit reluctant to add a linux box, but seems no choice.  :-)

Cheers !

Finally settled. Found the product "Remote Print Manager"  at http://lpd.brooksnet.com/index.html

It handles the work perfectly, convert PCL coding into right laypout in PDF output.

It cost some money but worth it.  

Cheers !

Good solution, although not the windows version I prefer.