I found this on another site. It's the only thing I have tried that allowed my Lexmark 5400 series to work. Good Luck!
"I recently upgraded to Leopard and saw that I could not print in Microsoft Word or Safari or anything else none the less.... I would click print and the programs would close unexpectedly. Here is the fix.... go to Library/Printers/Lexmark/PDEs you will see some plugins... IJAdvancedOptions.plugin, IJColorOptions.plugin, IJPrinterServices.plugin, IJPrintQuality.plugin... ok now what to do to make the freaking printer work?? rename all those to .plugindisabled at the end.. restart your machine.. then welcome back to printing goodness untill lexmark decides that we are cool enough to write drivers for again
Just my experience...hope this helps lots of us."