diff --git a/libtirpc/src/auth_sspi.c b/libtirpc/src/auth_sspi.c
index e53b37a..d618199 100644
--- a/libtirpc/src/auth_sspi.c
+++ b/libtirpc/src/auth_sspi.c
@@ -351,8 +351,19 @@ authsspi_refresh(AUTH *auth, void *tmp)
 
 	gd = AUTH_PRIVATE(auth);
 
-	if (gd->established)
+	if (gd->established && tmp == NULL)
 		return (TRUE);
+    else if (tmp) {
+        log_debug("trying to refresh credentials\n");
+        DeleteSecurityContext(&gd->ctx);
+        sspi_release_buffer(&gd->gc.gc_ctx);
+        SecInvalidateHandle(&gd->ctx);
+        mem_free(gd->gc_wire_verf.value, gd->gc_wire_verf.length);
+        gd->gc_wire_verf.value = NULL;
+        gd->gc_wire_verf.length = 0;
+        gd->established = FALSE;        
+        gd->gc.gc_proc = RPCSEC_SSPI_INIT;
+    }
 
 	/* GSS context establishment loop. */
 	memset(&gr, 0, sizeof(gr));
diff --git a/libtirpc/src/clnt_vc.c b/libtirpc/src/clnt_vc.c
index d0c0ea6..9ae30d6 100644
--- a/libtirpc/src/clnt_vc.c
+++ b/libtirpc/src/clnt_vc.c
@@ -159,9 +159,10 @@ static cond_t   *vc_cv;
 
 #define acquire_fd_lock(fd) { \
 	mutex_lock(&clnt_fd_lock); \
-	while (vc_fd_locks[WINSOCK_HANDLE_HASH(fd)]) \
+	while (vc_fd_locks[WINSOCK_HANDLE_HASH(fd)] && \
+            vc_fd_locks[WINSOCK_HANDLE_HASH(fd)] != GetCurrentThreadId()) \
 		cond_wait(&vc_cv[WINSOCK_HANDLE_HASH(fd)], &clnt_fd_lock); \
-	vc_fd_locks[WINSOCK_HANDLE_HASH(fd)] = 1; \
+	vc_fd_locks[WINSOCK_HANDLE_HASH(fd)] = GetCurrentThreadId(); \
 	mutex_unlock(&clnt_fd_lock); \
 }
 
@@ -554,10 +555,11 @@ call_again:
 	
 	while (TRUE) {
         mutex_lock(&clnt_fd_lock);
-	    while (vc_fd_locks[WINSOCK_HANDLE_HASH(ct->ct_fd)] || 
+	    while ((vc_fd_locks[WINSOCK_HANDLE_HASH(ct->ct_fd)] && 
+                vc_fd_locks[WINSOCK_HANDLE_HASH(ct->ct_fd)] != GetCurrentThreadId()) || 
                 (ct->reply_msg.rm_xid && ct->reply_msg.rm_xid != x_id))
 		    cond_wait(&vc_cv[WINSOCK_HANDLE_HASH(ct->ct_fd)], &clnt_fd_lock);
-	    vc_fd_locks[WINSOCK_HANDLE_HASH(ct->ct_fd)] = 1;
+	    vc_fd_locks[WINSOCK_HANDLE_HASH(ct->ct_fd)] = GetCurrentThreadId();
 	    mutex_unlock(&clnt_fd_lock);
 
         xdrs->x_op = XDR_DECODE;