diff --git a/appl/ftp/ftpd/krb4.c b/appl/ftp/ftpd/krb4.c
index 47669ad48..50f2fb5de 100644
--- a/appl/ftp/ftpd/krb4.c
+++ b/appl/ftp/ftpd/krb4.c
@@ -94,10 +94,10 @@ int krb4_adat(char *auth)
     }
     tkt.length = len;
 
-    k_getsockinst(0, inst);
+    k_getsockinst(0, inst, sizeof(inst));
     kerror = krb_rd_req(&tkt, "ftp", inst, 0, &auth_dat, "");
     if(kerror == RD_AP_UNDEC){
-	k_getsockinst(0, inst);
+	k_getsockinst(0, inst, sizeof(inst));
 	kerror = krb_rd_req(&tkt, "rcmd", inst, 0, &auth_dat, "");
     }
 
diff --git a/appl/kx/kxd.c b/appl/kx/kxd.c
index 2419938b6..d18594a4d 100644
--- a/appl/kx/kxd.c
+++ b/appl/kx/kxd.c
@@ -125,7 +125,7 @@ recv_conn (int sock, des_cblock *key, des_key_schedule schedule,
 
      inaddr2str (thataddr->sin_addr, remotehost, sizeof(remotehost));
 
-     k_getsockinst (sock, instance);
+     k_getsockinst (sock, instance, sizeof(instance));
      status = krb_recvauth (KOPT_DO_MUTUAL, sock, &ticket, "rcmd", instance,
 			    thataddr, thisaddr, &auth, "", schedule,
 			    version);
diff --git a/appl/popper/pop_init.c b/appl/popper/pop_init.c
index a1a65f88c..ae28a7fef 100644
--- a/appl/popper/pop_init.c
+++ b/appl/popper/pop_init.c
@@ -19,7 +19,7 @@ krb_authenticate(POP *p, struct sockaddr_in *addr)
     char version[9];
     int auth;
   
-    k_getsockinst (0, instance);
+    k_getsockinst (0, instance, sizeof(instance));
     auth = krb_recvauth(0L, 0, &ticket, "pop", instance,
                         addr, (struct sockaddr_in *) NULL,
                         &p->kdata, "", schedule, version);
diff --git a/appl/telnet/libtelnet/kerberos.c b/appl/telnet/libtelnet/kerberos.c
index 10672c9cf..6e8311cfe 100644
--- a/appl/telnet/libtelnet/kerberos.c
+++ b/appl/telnet/libtelnet/kerberos.c
@@ -290,7 +290,7 @@ kerberos4_is(Authenticator *ap, unsigned char *data, int cnt)
 	    printd(auth.dat, auth.length);
 	    printf("\r\n");
 	}
-	k_getsockinst(0, instance); /* Telnetd uses socket 0 */
+	k_getsockinst(0, instance, sizeof(instance));
 	if (r = krb_rd_req(&auth, KRB_SERVICE_NAME,
 			   instance, 0, &adat, "")) {
 	    if (auth_debug_mode)