oops, true this. I thought it was to do with endian.h - which seems to exist and be included. Mucho apologies.
doing the fix mentioned earlier (some macro + another include) seems to have made it compile, but, not tested it out yet.
For reference, also on Lenny debian.
kokade:~/bc/pushpool-0.5.1# catproc/version
Linux version 2.6.26-2-amd64 (Debian 2.6.26-26lenny2) (
dannf@debian.org) (gcc version 4.1.3 20080704 (prerelease) (Debian 4.1.2-25)) #1 SMP Tue Jan 25 05:59:43 UTC 2011