Tested on Ubuntu Precise (kernel 3.2.0) and Ubuntu Natty (kernel 2.6.38) amd64.
I have disabled the PCMCIA driver in the makefile; there are many changes that need to be made in order for it to be compatible with newer kernels, see:
http://www.kernel.org/doc/Documentation/pcmcia/driver-changes.txt
...and I don't have access to an iBurst PCMCIA modem for testing.
I also made some changes to the ibapplet scripts; in /proc/net/wireless, the interface name does not appear at the start of the line, it is prefixed by a couple of spaces, also, the signal level value is often suffixed by a full-stop.
3.2.0 patch