The Linux/IrDA project has undertaken some changes in the program code, which you should know to understand some confusions.
For 2.0.x kernels Linux/IrDA support worked in a totally other way and is no longer supported by the Linux/IrDA project. Since 2.1.131 and 2.2.0 is part of the kernel. Please note that the status of the project just changed from experimental to stable with 2.2.10 kernels.
Some caveats are sometimes caused by changes of the following parameters (Hope I have got them alright now, they confused me sometimes, too):
the major device number of the irda device changed from 61 to 161 (and from 60 to 160?)
some task of irmanager are now achieved by irattach
the device name ircomm_tty changed to ircomm-tty
the device name irnine changed to ircomm_new