diff -r c6cf20b09043 -r b3a89736b23e src/server/daemon/vfs.c
--- a/src/server/daemon/vfs.c	Sun Mar 17 17:54:20 2013 +0100
+++ b/src/server/daemon/vfs.c	Sun Mar 17 19:19:57 2013 +0100
@@ -160,7 +160,7 @@
     uid_t uid; // uid and gid will be initialized by sys_acl_check
     gid_t gid;
     if(sys_acl_check(ctx, access_mask, &uid, &gid)) {
-        return NULL;
+        return -1;
     }
     
     // stat
@@ -340,7 +340,7 @@
     uid_t uid; // uid and gid will be initialized by sys_acl_check
     gid_t gid;
     if(sys_acl_check(ctx, access_mask, &uid, &gid)) {
-        return NULL;
+        return -1;
     }
     
     // do path operation