diff --git a/resource.c b/resource.c
index edd5a16f..31acc569 100644
--- a/resource.c
+++ b/resource.c
@@ -21,9 +21,6 @@
 MEMB(resource_storage, coap_resource_t, COAP_MAX_RESOURCES);
 MEMB(attribute_storage, coap_attr_t, COAP_MAX_ATTRIBUTES);
 MEMB(subscription_storage, coap_subscription_t, COAP_MAX_SUBSCRIBERS);
-#endif /* WITH_CONTIKI */
-
-#define min(a,b) ((a) < (b) ? (a) : (b))
 
 void
 coap_resources_init() {
@@ -31,6 +28,9 @@ coap_resources_init() {
   memb_init(&attribute_storage);
   memb_init(&subscription_storage);
 }
+#endif /* WITH_CONTIKI */
+
+#define min(a,b) ((a) < (b) ? (a) : (b))
 
 /** 
  * Prints the names of all known resources to @p buf. This function
@@ -93,10 +93,7 @@ coap_resource_init(const unsigned char *uri, size_t len) {
   if (r) {
     memset(r, 0, sizeof(coap_resource_t));
 
-#ifndef WITH_CONTIKI
-    #warning "no resource list"
-    /* FIXME: initialize r->subscribers */
-#else /* WITH_CONTIKI */
+#ifdef WITH_CONTIKI
     LIST_STRUCT_INIT(r, link_attr);
     LIST_STRUCT_INIT(r, subscribers);
 #endif /* WITH_CONTIKI */
@@ -174,7 +171,9 @@ int
 coap_delete_resource(coap_context_t *context, coap_key_t key) {
   coap_resource_t *resource;
   coap_attr_t *attr;
+#ifdef WITH_CONTIKI
   coap_subscription_t *obs;
+#endif
 
   if (!context)
     return 0;
@@ -289,7 +288,11 @@ coap_find_observer(coap_resource_t *resource, const coap_address_t *peer,
   assert(resource);
   assert(peer);
 
+#ifndef WITH_CONTIKI
+  LL_FOREACH(resource->subscribers, s) {
+#else /* WITH_CONTIKI */
   for (s = list_head(resource->subscribers); s; s = list_item_next(s)) {
+#endif /* WITH_CONTIKI */
     if (coap_address_equals(&s->subscriber, peer)
 	&& (!token || (token->length == s->token_length 
 		       && memcmp(token->s, s->token, token->length) == 0)))
@@ -317,8 +320,7 @@ coap_add_observer(coap_resource_t *resource,
   /* s points to a different subscription, so we have to create
    * another one. */
 #ifndef WITH_CONTIKI
-  /* FIXME */
-  s = NULL;
+  s = (coap_subscription_t *)coap_malloc(sizeof(coap_subscription_t));
 #else /* WITH_CONTIKI */
   s = memb_alloc(&subscription_storage);
 #endif /* WITH_CONTIKI */
@@ -336,7 +338,7 @@ coap_add_observer(coap_resource_t *resource,
 
   /* add subscriber to resource */
 #ifndef WITH_CONTIKI
-  /* FIXME */
+  LL_PREPEND(resource->subscribers, s);
 #else /* WITH_CONTIKI */
   list_add(resource->subscribers, s);
 #endif /* WITH_CONTIKI */
@@ -352,10 +354,18 @@ void
   s = coap_find_observer(resource, observer, token);
 
   if (s) {
+#ifndef WITH_CONTIKI
+    LL_DELETE(resource->subscribers, s);
+#else /* WITH_CONTIKI */
     list_remove(resource->subscribers, s);
+#endif /* WITH_CONTIKI */
 
     /* FIXME: notify observer that its subscription has been removed */
+#ifndef WITH_CONTIKI
+    coap_free(s);
+#else /* WITH_CONTIKI */
     memb_free(&subscription_storage, s);
+#endif /* WITH_CONTIKI */
   }
 }
 
@@ -394,7 +404,7 @@ coap_check_notify(coap_context_t *context) {
 
 #ifndef WITH_CONTIKI
       /* FIXME: */
-      /* for {obs = r->subscribers; obs; obs = obs->next) { */
+	LL_FOREACH(r->subscribers, obs) {
 #else /* WITH_CONTIKI */
       for (obs = list_head(r->subscribers); obs; obs = list_item_next(obs)) {
 #endif /* WITH_CONTIKI */
diff --git a/resource.h b/resource.h
index b4993cdc..4bbdc10c 100644
--- a/resource.h
+++ b/resource.h
@@ -64,6 +64,7 @@ typedef struct coap_resource_t {
   coap_key_t key;	/**< the actual key bytes for this resource */
 
 #ifndef WITH_CONTIKI
+  UT_hash_handle hh;
   coap_attr_t *link_attr; /**< attributes to be included with the link format */
   coap_subscription_t *subscribers; /**< list of observers for this resource */
 #else /* WITH_CONTIKI */
diff --git a/subscribe.h b/subscribe.h
index 3c7fcf91..31f33fc3 100644
--- a/subscribe.h
+++ b/subscribe.h
@@ -19,6 +19,24 @@
  * @{
  */
 
+#ifndef COAP_OBS_MAX_NON
+/**
+ * Number of notifications that may be sent non-confirmable before a
+ * confirmable message is sent to detect if observers are alive. The
+ * maximum allowed value here is @c 15.
+ */
+#define COAP_OBS_MAX_NON   5
+#endif /* COAP_OBS_MAX_NON */
+
+#ifndef COAP_OBS_MAX_FAIL
+/**
+ * Number of confirmable notifications that may fail (i.e. time out
+ * without being ACKed) before an observer is removed. The maximum
+ * value for COAP_OBS_MAX_FAIL is @c 3.
+ */
+#define COAP_OBS_MAX_FAIL  3
+#endif /* COAP_OBS_MAX_FAIL */
+
 /** Subscriber information */
 typedef struct coap_subscription_t {
   struct coap_subscription_t *next; /**< next element in linked list */