diff --git a/infrastructure-centred/owlps-aggregator/Makefile b/infrastructure-centred/owlps-aggregator/Makefile
index 521ab10..3d7157d 100644
--- a/infrastructure-centred/owlps-aggregator/Makefile
+++ b/infrastructure-centred/owlps-aggregator/Makefile
@@ -24,7 +24,7 @@ CFLAGS=-O2 -Wall -Wextra -Wstrict-prototypes -O -I.
 DEPFLAGS=-MMD
 XCFLAGS=$(CFLAGS) $(DEPFLAGS) $(WARN) $(HEADERS)
 PICFLAG=-fPIC
-OWLPSFLAGS = -D TIMESTAMP
+OWLPSFLAGS = -D USE_TIMESTAMP
 LIBS = -pthread -lconfuse -L../../libowlps -lowlps
 LDFLAGS = $(LIBS) $(OWLPSFLAGS)
 
diff --git a/infrastructure-centred/owlps-aggregator/owlps-aggregator.h b/infrastructure-centred/owlps-aggregator/owlps-aggregator.h
index 2c56dc5..c4cb28c 100644
--- a/infrastructure-centred/owlps-aggregator/owlps-aggregator.h
+++ b/infrastructure-centred/owlps-aggregator/owlps-aggregator.h
@@ -11,7 +11,7 @@
 #define DEBUG
 
 // Uncomment to output the timestamp on each line of the output file:
-//#define TIMESTAMP
+//#define USE_TIMESTAMP
 
 
 /* Arguments & program configuration */
diff --git a/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c b/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c
index 48b9f34..4d4b4f8 100644
--- a/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c
+++ b/infrastructure-centred/owlps-aggregator/owlps-aggregatord.c
@@ -446,11 +446,11 @@ void* monitor_couples()
                   putchar('\n') ;
 #endif // DEBUG
 
-#ifdef TIMESTAMP
+#ifdef USE_TIMESTAMP
                   // Print request mobile timestamp to the output file
                   fprintf(fd, "%llu;",
                           timeval_to_ms(couple_ptr->request_time)) ;
-#endif // TIMESTAMP
+#endif // USE_TIMESTAMP
 
                   // Print mobile MAC address to the output file
                   mac_string =