diff --git a/harbour/contrib/libct/ctmath.h b/harbour/contrib/libct/ctmath.h
index 8d13d99236..25180630ae 100644
--- a/harbour/contrib/libct/ctmath.h
+++ b/harbour/contrib/libct/ctmath.h
@@ -54,7 +54,11 @@
 #ifndef _CTMATH_H
 #define _CTMATH_H
 
+#ifdef __DJGPP__
+#include <libm/math.h>
+#else
 #include <math.h>
+#endif
 #include <float.h>
 #include <limits.h>