If you find a bug, please send a bug report to the mailing list, including dmesg output, and which Linux version, and hardware you are using. Thank you!
Sometimes IrCOMM fails to connect (especially when both devices discover each other. You can disable discovering with echo 0 >/proc/sys/net/irda/discovery)
A CR (carriage return) character cannot be transfered between two linux boxes via IrCOMM with cat file >/dev/ircomm0 and cat /dev/ircomm0. It causes a strange thing and freezes your Linux box. Compiling the pc87108 device driver non modular crashes the kernel on boot. Temporary solution: compile the driver as a module
IrOBEX may eat some data on receive. The bug is most probably in the user-space side of IrOBEX.