Cannot build GDC 0.18 alpha

[Andrew Madigan]

I'm using the source from http://www.puremagic.com/~braddr/d/gdc/

I get the following error from make:

make[1]: Entering directory `/home/nnnnn/local/build/gcc-4.0.3/build/gcc'
make[1]: *** No rule to make target `d/idgen.dmdgen.o', needed by `d/idgen'. 
Stop.
make[1]: Leaving directory `/home/nnnnn/local/build/gcc-4.0.3/build/gcc'

Evironment:

Ubuntu Dapper
Linux Kernel 2.6.15-20-686
First Line of output from gcc --version:
gcc (GCC) 4.0.3 (gdc 0.17, using dmd 0.140)
GNU Make

As you can see this system was able to build gdc 0.17, is 0.18 not
buildable?