diff --git a/exec/totempg.c b/exec/totempg.c
index e2ce17f0..f723decf 100644
--- a/exec/totempg.c
+++ b/exec/totempg.c
@@ -1199,7 +1199,7 @@ int totempg_groups_mcast_groups (
 	const struct totempg_group *groups,
 	size_t groups_cnt,
 	const struct iovec *iovec,
-	size_t iov_len)
+	unsigned int iov_len)
 {
 	struct totempg_group_instance *instance;
 	unsigned short group_len[MAX_GROUPS_PER_MSG + 1];
@@ -1247,7 +1247,7 @@ int totempg_groups_send_ok_groups (
 	const struct totempg_group *groups,
 	size_t groups_cnt,
 	const struct iovec *iovec,
-	size_t iov_len)
+	unsigned int iov_len)
 {
 	struct totempg_group_instance *instance;
 	unsigned int size = 0;
diff --git a/include/corosync/evs.h b/include/corosync/evs.h
index f17903a3..68705ca8 100644
--- a/include/corosync/evs.h
+++ b/include/corosync/evs.h
@@ -142,7 +142,7 @@ cs_error_t evs_mcast_joined (
 	evs_handle_t handle,
 	evs_guarantee_t guarantee,
 	const struct iovec *iovec,
-	size_t iov_len);
+	unsigned int iov_len);
 
 /*
  * Multicast to specified groups.
@@ -155,7 +155,7 @@ cs_error_t evs_mcast_groups (
 	const struct evs_group *groups,
 	size_t group_cnt,
 	const struct iovec *iovec,
-	size_t iov_len);
+	unsigned int iov_len);
 
 /*
  * Get membership information from evs
diff --git a/include/corosync/totem/totempg.h b/include/corosync/totem/totempg.h
index b0f489c0..20e1189a 100644
--- a/include/corosync/totem/totempg.h
+++ b/include/corosync/totem/totempg.h
@@ -124,14 +124,14 @@ extern int totempg_groups_mcast_groups (
 	const struct totempg_group *groups,
 	size_t groups_cnt,
 	const struct iovec *iovec,
-	size_t iov_len);
+	unsigned int iov_len);
 
 extern int totempg_groups_send_ok_groups (
 	hdb_handle_t handle,
 	const struct totempg_group *groups,
 	size_t groups_cnt,
 	const struct iovec *iovec,
-	size_t iov_len);
+	unsigned int iov_len);
 	
 extern int totempg_ifaces_get (
 	unsigned int nodeid,
diff --git a/lib/evs.c b/lib/evs.c
index 5053b7a6..6f968358 100644
--- a/lib/evs.c
+++ b/lib/evs.c
@@ -413,7 +413,7 @@ evs_error_t evs_mcast_joined (
 	evs_handle_t handle,
 	evs_guarantee_t guarantee,
 	const struct iovec *iovec,
-	size_t iov_len)
+	unsigned int iov_len)
 {
 	int i;
 	evs_error_t error;
@@ -470,7 +470,7 @@ evs_error_t evs_mcast_groups (
 	const struct evs_group *groups,
 	size_t group_entries,
 	const struct iovec *iovec,
-	size_t iov_len)
+	unsigned int iov_len)
 {
 	int i;
 	evs_error_t error;
diff --git a/man/cpg_mcast_joined.3 b/man/cpg_mcast_joined.3
index 2c7c858f..3865dda6 100644
--- a/man/cpg_mcast_joined.3
+++ b/man/cpg_mcast_joined.3
@@ -102,7 +102,7 @@ is a standard socket structure described by:
 struct iovec
 {
         void *iov_base;     /* Pointer to data.  */
-        size_t iov_len;     /* Length of data.  */
+        unsigned int iov_len;     /* Length of data.  */
 };
 .ta
 .fi
diff --git a/man/evs_mcast_groups.3 b/man/evs_mcast_groups.3
index fca94f17..f3d28f9c 100644
--- a/man/evs_mcast_groups.3
+++ b/man/evs_mcast_groups.3
@@ -130,7 +130,7 @@ is a standard socket structure described by:
 struct iovec
 {
 	void *iov_base;     /* Pointer to data.  */
-	size_t iov_len;     /* Length of data.  */
+	unsigned int iov_len;     /* Length of data.  */
 };
 .ta
 .fi
diff --git a/man/evs_mcast_joined.3 b/man/evs_mcast_joined.3
index 4d2eeb5e..a685e8b1 100644
--- a/man/evs_mcast_joined.3
+++ b/man/evs_mcast_joined.3
@@ -103,7 +103,7 @@ is a standard socket structure described by:
 struct iovec
 {
 	void *iov_base;     /* Pointer to data.  */
-	size_t iov_len;     /* Length of data.  */
+	unsigned int iov_len;     /* Length of data.  */
 };
 .ta
 .fi