diff --git a/doxygen.cfg b/doxygen.cfg
index 6edc71333b..0d77ce20ab 100644
--- a/doxygen.cfg
+++ b/doxygen.cfg
@@ -1601,7 +1601,7 @@ INCLUDE_FILE_PATTERNS  =
 # undefined via #undef or recursively expanded use the := operator
 # instead of the = operator.
 
-PREDEFINED             = NFQ IPFW HAVE_PFRING HAVE_AF_PACKET PRELUDE HAVE_NAPATECH HAVE_DAG PROFILING
+PREDEFINED             = NFQ IPFW HAVE_PFRING HAVE_AF_PACKET PRELUDE HAVE_NAPATECH HAVE_DAG PROFILING UNITTESTS
 
 # If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then
 # this tag can be used to specify a list of macro names that should be expanded.