Where does what say it isn't compatible? The printer cd, box, docs? Or something on your computer?
According to this http://support.apple.com/kb/HT3669 your printer is supported.
Try connecting the printer with a cable, forget about any CD that comes with the printer, and opening the Print & Scan pane in > System Preferences. Click 'Add Printer' and see if your printer is shown.
If not, run software update and try again.
To get full functionality download and install the latest software below:
Be sure to select HP Recommended Software while installing, then reboot and run Software Update.