Index: src/wal.c
==================================================================
--- src/wal.c
+++ src/wal.c
@@ -2900,15 +2900,17 @@
 ** SQLITE_OK is returned if no error is encountered (regardless of whether
 ** or not pWal->hdr.mxFrame is modified). An SQLite error code is returned
 ** if an error occurs.
 */
 static int walRestartLog(Wal *pWal){
+  volatile WalCkptInfo *pInfo = walCkptInfo(pWal);
   int rc = SQLITE_OK;
   int cnt;
 
-  if( pWal->readLock==0 ){
-    volatile WalCkptInfo *pInfo = walCkptInfo(pWal);
+  if( pWal->readLock==0 
+   || (walIsServer(pWal) && pInfo->nBackfill==pWal->hdr.mxFrame)
+  ){
     assert( pInfo->nBackfill==pWal->hdr.mxFrame );
     if( pInfo->nBackfill>0 ){
       u32 salt1;
       sqlite3_randomness(4, &salt1);
       rc = walLockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
@@ -2926,10 +2928,11 @@
         walUnlockExclusive(pWal, WAL_READ_LOCK(1), WAL_NREADER-1);
       }else if( rc!=SQLITE_BUSY ){
         return rc;
       }
     }
+    if( walIsServer(pWal) ) return rc;
     walUnlockShared(pWal, WAL_READ_LOCK(0));
     pWal->readLock = -1;
     cnt = 0;
     do{
       int notUsed;

Index: test/serverwal.test
==================================================================
--- test/serverwal.test
+++ test/serverwal.test
@@ -34,10 +34,11 @@
 do_test 1.4 {
   db close
   glob test.db*
 } {test.db}
 
+#-------------------------------------------------------------------------
 # Two concurrent transactions.
 #
 do_test 2.0 {
   sqlite3 db  test.db
   sqlite3 db2 test.db
@@ -57,8 +58,33 @@
 } {}
 do_test 2.2 {
   execsql COMMIT db
   execsql COMMIT db2
 } {}
+db close
+
+#-------------------------------------------------------------------------
+# That the wal file can be wrapped around.
+#
+reset_db
+do_execsql_test 3.0 {
+  PRAGMA journal_mode = wal;
+  CREATE TABLE ttt(a, b);
+  INSERT INTO ttt VALUES(1, 2);
+  INSERT INTO ttt VALUES(3, 4);
+  INSERT INTO ttt VALUES(5, 6);
+  INSERT INTO ttt VALUES(7, 8);
+  INSERT INTO ttt VALUES(9, 10);
+} {wal}
 
+do_test 3.1 {
+  set N [file size test.db-wal]
+  execsql {
+    PRAGMA wal_checkpoint;
+    INSERT INTO ttt VALUES(11, 12);
+    INSERT INTO ttt VALUES(13, 14);
+  }
+  expr {$N == [file size test.db-wal]}
+} {1}
 
 finish_test
+