HP Printers trying to do 802.1x but failing with timeouts

Hello, I have a working 802.1x setup on the wired network of our office and everything is fine for Linux stations, Apple notebooks and the few windows notebooks we have. The Linux stations and the apple notebooks are doing EAP-TLS. And my idea was to have the printers we use do the same. But with the printers I get a lot of timeouts during authentication and to me it looks like the printer is really having a big issue handling all the certificate things etc. Does anyone here have experience in setting this up? Would it be an idea to get a newer printserver into the printers? I'm looking at the JetDirect 635 (J7961G). Jan Hugo Prins