diff --git a/src/core/snmp/mib2.c b/src/core/snmp/mib2.c
index afb3c312..c7ee1116 100644
--- a/src/core/snmp/mib2.c
+++ b/src/core/snmp/mib2.c
@@ -731,8 +731,10 @@ const struct mib_array_node mgmt = {
 
 /* internet .1.3.6.1 */
 #if SNMP_PRIVATE_MIB
+/* When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB. */
 s32_t internet_ids[2] = { 2, 4 };
-struct mib_node* const internet_nodes[2] = { (struct mib_node* const)&mgmt, (struct mib_node* const)&private };
+struct mib_node* const internet_nodes[2] = { (struct mib_node* const)&mgmt, (struct mib_node* const)&mib_private };
 const struct mib_array_node internet = {
   &noleafs_get_object_def,
   &noleafs_get_value,
diff --git a/src/core/snmp/msg_in.c b/src/core/snmp/msg_in.c
index 194b67df..05d30f91 100644
--- a/src/core/snmp/msg_in.c
+++ b/src/core/snmp/msg_in.c
@@ -88,6 +88,15 @@ snmp_init(void)
     msg_ps++;
   }
   trap_msg.pcb = snmp1_pcb;
+
+#ifdef SNMP_PRIVATE_MIB_INIT
+  /* If defined, rhis must be a function-like define to initialize the
+   * private MIB after the stack has been initialized.
+   * The private MIB can also be initialized in tcpip_callback (or after
+   * the stack is initialized), this define is only for convenience. */
+  SNMP_PRIVATE_MIB_INIT();
+#endif /* SNMP_PRIVATE_MIB_INIT */
+
   /* The coldstart trap will only be output
      if our outgoing interface is up & configured  */
   snmp_coldstart_trap();
diff --git a/src/include/lwip/opt.h b/src/include/lwip/opt.h
index c23318de..3dd7fe84 100644
--- a/src/include/lwip/opt.h
+++ b/src/include/lwip/opt.h
@@ -627,6 +627,8 @@
 
 /**
  * SNMP_PRIVATE_MIB: 
+ * When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB.
  */
 #ifndef SNMP_PRIVATE_MIB
 #define SNMP_PRIVATE_MIB                0
diff --git a/src/include/lwip/snmp_msg.h b/src/include/lwip/snmp_msg.h
index 49b5e409..8842893a 100644
--- a/src/include/lwip/snmp_msg.h
+++ b/src/include/lwip/snmp_msg.h
@@ -44,6 +44,8 @@
 #if LWIP_SNMP
 
 #if SNMP_PRIVATE_MIB
+/* When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB. */
 #include "private_mib.h"
 #endif
 
diff --git a/src/include/lwip/snmp_structs.h b/src/include/lwip/snmp_structs.h
index 9f3f8a94..613d6de2 100644
--- a/src/include/lwip/snmp_structs.h
+++ b/src/include/lwip/snmp_structs.h
@@ -44,6 +44,8 @@
 #include "lwip/snmp.h"
 
 #if SNMP_PRIVATE_MIB
+/* When using a private MIB, you have to create a file 'private_mib.h' that contains
+ * a 'struct mib_array_node mib_private' which contains your MIB. */
 #include "private_mib.h"
 #endif