diff --git a/simple.make b/simple.make
index 9b20d032..2f23bd65 100644
--- a/simple.make
+++ b/simple.make
@@ -183,7 +183,7 @@ M2_PLANET_SOURCES =						\
 	    -e 's@^(#include.*)@/* \1 */@'		\
 	    $<						\
 	| $(CC) -E -I include				\
-	    -D POINTER_CELLS=1				\
+	    -D POINTER_CELLS=0				\
 	    -D __M2_PLANET__=1				\
 	    -D 'MES_VERSION="git"'			\
 	    -D 'MES_PKGDATADIR="/usr/local/share/mes"'	\
@@ -209,7 +209,7 @@ M2_PLANET_SOURCES =						\
 	    -e 's@^(#include.*)@/* \1 */@'		\
 	    $<						\
 	| $(CC) -E -I include				\
-	    -D POINTER_CELLS=1				\
+	    -D POINTER_CELLS=0				\
 	    -D __M2_PLANET__=1				\
 	    -D 'MES_VERSION="git"'			\
 	    -D 'MES_PKGDATADIR="/usr/local/share/mes"'	\
diff --git a/src/gc.c b/src/gc.c
index 98986661..3f0d47da 100644
--- a/src/gc.c
+++ b/src/gc.c
@@ -67,6 +67,8 @@ cell_bytes (SCM x)
 #if POINTER_CELLS
   char *p = x;
   return p + (2 * sizeof (long));
+#elif __M2_PLANET__
+  CELL (x) + 8;
 #else
   return &CDR (x);
 #endif