I did a clean install of Ubuntu 11.10 (64bit) and a checkout of the current Git repo. When compiling (./build -j 8) I get an error that histedit.h can not be found (client.h:48) in JsonDB.
I've installed libedit-dev and the problem disappeared. Not sure if this is actually a bug, but this dependency should probably be added to the configuration (or at least add it to the wiki that this must be installed first).