There is a Generic PCL Laser printer driver included with 10.6. If the Ricoh supports PCL, and there is every likelihood it does, then you can use this driver. To create a printer queue, you should be able to select IP > HP Jetdirect-Socket (which is the same as RAW Port 9100 that Windows will be using). You then enter the IP address of the Ricoh and in the Print Using menu select Generic PCL Laser.
Note that this driver will only print in B&W. Judging by the Ricoh's model name, this is a color copier so if you want to print in color, you can use the pxlmono package available via this
link. Read the information on this page carefully as you need all three packages shown.
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