diff --git a/src/if_mzsch.c b/src/if_mzsch.c
index ea04705..0884c9f 100644
--- a/src/if_mzsch.c
+++ b/src/if_mzsch.c
@@ -3084,6 +3084,14 @@
 
 	MZ_GC_UNREG();
     }
+    else if (vim_value->v_type == VAR_SPECIAL)
+    {
+	if (vim_value->vval.v_number <= VVAL_TRUE)
+	    result = scheme_make_integer((long)vim_value->vval.v_number);
+	else
+	    result = scheme_null;
+	MZ_GC_CHECK();
+    }
     else
     {
 	result = scheme_void;
@@ -3148,8 +3156,8 @@
 	copy_tv(found, tv);
     else if (SCHEME_VOIDP(obj))
     {
-	tv->v_type = VAR_NUMBER;
-	tv->vval.v_number = 0;
+	tv->v_type = VAR_SPECIAL;
+	tv->vval.v_number = VVAL_NULL;
     }
     else if (SCHEME_INTP(obj))
     {
@@ -3158,7 +3166,7 @@
     }
     else if (SCHEME_BOOLP(obj))
     {
-	tv->v_type = VAR_NUMBER;
+	tv->v_type = VAR_SPECIAL;
 	tv->vval.v_number = SCHEME_TRUEP(obj);
     }
 # ifdef FEAT_FLOAT