[Asterisk-Users] Error with dot when making progdocs

[David Carr]

I have doxygen installed as such

rpm -q doxygen
doxygen-1.2.18-3

but cannot make progdocs without errors...

Generating code for file vmodem.h...
Generating code for file zonedata.c...
Generating code for file zonedata.h...
Generating file documentation...
Generating docs for file acl.c...
sh: line 1: dot: command not found
Problems running dot. Check your installation!
sh: line 1: dot: command not found
Problems running dot. Check your installation!
Generating docs for file acl.h...
sh: line 1: dot: command not found
Problems running dot. Check your installation!

Does anyone know what dot is and what might be wrong with my installation?