I have been trying to compile the externals from cvs today, and the "sprinkler" object halts the compile each time due to an undefined environment variable, "PACKAGE_VERSION". It turns out the makefile for sprinkler sets this, but it doesn't get set in the actual externals/build/linux/makefile that I use to compile all the externs at one time. I simply took the "DEFS=..." portion from the sprinkler/makefile (which defines the PACKAGE_VERSION var, among others) and added that to the build/linux/makefile, then added "$(DEFS)" to the compiler flags variable in build/linux/makefile.
I don't know what caused this to occur, perhaps this runs on older versions of gcc fine? I also don't know a more graceful solution to this problem. In any case, my specs are: Linux 2.6.3, gcc 3.3.2, fedora stable/unstable mix, Athlon, 512Mb ram. I think the problem is probably newer gcc compatibility, since that seems to be the big problem with the other source code hiccups in cvs.
Anyway, I hope this helps someone!
-John Lamb