A940 printer problem PCL or postscript

I support a software application that is having problems printing on a Dell A940 printer.  My software communicates directly with the Windows print spooler.  Once it hits the print spooler, my application relinquishes all control to the spooler and printer driver.  One of my users just purchased a Dell 2400 with WinXP Home Edition and and an A940 printer.  They are responsible for purchasing their own hardware and installing the software.  Now they can't print using my application.  The print job appears in the printer window, the printer says it is printing, but nothing prints.  Also, my application does not recognize postscrpt printer drivers, only PCL printer drivers.  Does anyone know what kind of printer driver the A940 uses?  Also, my users are scattered statewide, so I am not watching their printer installation process.  Does anyone know if there is a choice as to the type of printer driver during the installation process?  Thanks for your help.