diff --git a/include/minix/callnr.h b/include/minix/callnr.h
index 2356075f7..997b36816 100644
--- a/include/minix/callnr.h
+++ b/include/minix/callnr.h
@@ -61,10 +61,6 @@
 
 #define NR_PM_CALLS		48	/* highest number from base plus one */
 
-/* Field names for the getprocnr(2) call. */
-#define PM_GETPROCNR_PID	m1_i1	/* pid_t */
-#define PM_GETPROCNR_ENDPT	m1_i1	/* endpoint_t */
-
 /* Field names for the getepinfo(2) call. */
 #define PM_GETEPINFO_ENDPT	m1_i1	/* endpoint_t */
 #define PM_GETEPINFO_UID	m1_i1	/* uid_t */
diff --git a/include/minix/ipc.h b/include/minix/ipc.h
index 927091b27..c9dc5f464 100644
--- a/include/minix/ipc.h
+++ b/include/minix/ipc.h
@@ -380,6 +380,20 @@ typedef struct {
 } mess_lc_vfs_umount;
 _ASSERT_MSG_SIZE(mess_lc_vfs_umount);
 
+typedef struct {
+	pid_t pid;
+
+	uint8_t padding[52];
+} mess_lsys_pm_getprocnr;
+_ASSERT_MSG_SIZE(mess_lsys_pm_getprocnr);
+
+typedef struct {
+	endpoint_t endpt;
+
+	uint8_t padding[52];
+} mess_pm_lsys_getprocnr;
+_ASSERT_MSG_SIZE(mess_pm_lsys_getprocnr);
+
 typedef struct {
 	endpoint_t endpt;
 	cp_grant_id_t grant;
@@ -883,10 +897,14 @@ typedef struct {
 		mess_lc_vfs_umask	m_lc_vfs_umask;
 		mess_lc_vfs_umount	m_lc_vfs_umount;
 
+		mess_lsys_pm_getprocnr	m_lsys_pm_getprocnr;
+
 		mess_lsys_vfs_checkperms m_lsys_vfs_checkperms;
 		mess_lsys_vfs_copyfd	m_lsys_vfs_copyfd;
 		mess_lsys_vfs_mapdriver	m_lsys_vfs_mapdriver;
 
+		mess_pm_lsys_getprocnr	m_pm_lsys_getprocnr;
+
 		mess_vfs_fs_breadwrite	m_vfs_fs_breadwrite;
 		mess_vfs_fs_chmod	m_vfs_fs_chmod;
 		mess_vfs_fs_chown	m_vfs_fs_chown;
diff --git a/lib/libsys/getprocnr.c b/lib/libsys/getprocnr.c
index 2750aed30..ddaa52f37 100644
--- a/lib/libsys/getprocnr.c
+++ b/lib/libsys/getprocnr.c
@@ -9,11 +9,11 @@ getprocnr(pid_t pid, endpoint_t *proc_e)
 	int r;
 
 	memset(&m, 0, sizeof(m));
-	m.PM_GETPROCNR_PID = pid;
+	m.m_lsys_pm_getprocnr.pid = pid;
 
 	if ((r = _taskcall(PM_PROC_NR, PM_GETPROCNR, &m)) < 0)
 		return r;
 
-	*proc_e = m.PM_GETPROCNR_ENDPT;
+	*proc_e = m.m_pm_lsys_getprocnr.endpt;
 	return r;
 }
diff --git a/servers/pm/misc.c b/servers/pm/misc.c
index fcdda46a2..12d80ee0a 100644
--- a/servers/pm/misc.c
+++ b/servers/pm/misc.c
@@ -175,10 +175,10 @@ int do_getprocnr(void)
 	return EPERM;
   }
 
-  if ((rmp = find_proc(m_in.PM_GETPROCNR_PID)) == NULL)
+  if ((rmp = find_proc(m_in.m_lsys_pm_getprocnr.pid)) == NULL)
 	return(ESRCH);
 
-  mp->mp_reply.PM_GETPROCNR_ENDPT = rmp->mp_endpoint;
+  mp->mp_reply.m_pm_lsys_getprocnr.endpt = rmp->mp_endpoint;
   return(OK);
 }