diff --git a/source/smbd/open.c b/source/smbd/open.c
index f450e74e58c..cebb37ab291 100644
--- a/source/smbd/open.c
+++ b/source/smbd/open.c
@@ -48,8 +48,8 @@ static int fd_open(struct connection_struct *conn, char *fname,
 		fd = conn->vfs_ops.open(conn,dos_to_unix(fname,False),flags,mode);
 	}
 
-	DEBUG(10,("fd_open: name %s, mode = %d, fd = %d. %s\n", fname, (int)mode, fd,
-		(fd == -1) ? strerror(errno) : "" ));
+	DEBUG(10,("fd_open: name %s, flags = 0%o mode = 0%o, fd = %d. %s\n", fname,
+		flags, (int)mode, fd, (fd == -1) ? strerror(errno) : "" ));
 
 	return fd;
 }
@@ -647,7 +647,22 @@ files_struct *open_file_shared(connection_struct *conn,char *fname, SMB_STRUCT_S
 			flags = O_RDWR; 
 			break;
 		default:
-			flags = O_RDONLY;
+			/*
+			 * This little piece of insanity is inspired by the
+			 * fact that an NT client can open a file for O_RDONLY,
+			 * but set the create disposition to FILE_EXISTS_TRUNCATE.
+			 * If the client *can* write to the file, then it expects to
+			 * truncate the file, even though it is opening for readonly.
+			 * Quicken uses this stupid trick in backup file creation...
+			 * Thanks *greatly* to "David W. Chapman Jr." <dwcjr@inethouston.net>
+			 * for helping track this one down. It didn't bite us in 2.0.x
+			 * as we always opened files read-write in that release. JRA.
+			 */
+
+			if (flags2 & O_TRUNC)
+				flags = O_RDWR; 
+			else
+				flags = O_RDONLY;
 			break;
 	}
 
diff --git a/source/utils/torture.c b/source/utils/torture.c
index 446bf7eaf22..871e2adfc34 100644
--- a/source/utils/torture.c
+++ b/source/utils/torture.c
@@ -2397,6 +2397,8 @@ static void run_opentest(int dummy)
     int fnum1, fnum2;
 	uint8 eclass;
 	uint32 errnum;
+	char buf[20];
+	size_t fsize;
 
     printf("starting open test\n");
 
@@ -2470,11 +2472,76 @@ static void run_opentest(int dummy)
 		printf("correct error code ERRDOS/ERRbadshare returned\n");
 	}
 
+    if (!cli_close(&cli1, fnum1)) {
+        printf("close2 failed (%s)\n", cli_errstr(&cli1));
+        return;
+    }
+
+	cli_unlink(&cli1, fname);
+
+    printf("finished open test 2\n");
+
+	/* Test truncate open disposition on file opened for read. */
+
+    fnum1 = cli_open(&cli1, fname, O_RDWR|O_CREAT|O_EXCL, DENY_NONE);
+    if (fnum1 == -1) {
+        printf("(3) open (1) of %s failed (%s)\n", fname, cli_errstr(&cli1));
+        return;
+    }
+
+	/* write 20 bytes. */
+
+	memset(buf, '\0', 20);
+
+	if (cli_write(&cli1, fnum1, 0, buf, 0, 20) != 20) {
+		printf("write failed (%s)\n", cli_errstr(&cli1));
+	}
+
+    if (!cli_close(&cli1, fnum1)) {
+        printf("(3) close1 failed (%s)\n", cli_errstr(&cli1));
+        return;
+    }
+
+	/* Ensure size == 20. */
+	if (!cli_getatr(&cli1, fname, NULL, &fsize, NULL)) {
+		printf("(3) getatr failed (%s)\n", cli_errstr(&cli1));
+		return;
+	}
+
+	if (fsize != 20) {
+		printf("(3) file size != 20\n");
+		return;
+	}
+
+	/* Now test if we can truncate a file opened for readonly. */
+
+	fnum1 = cli_open(&cli1, fname, O_RDONLY|O_TRUNC, DENY_NONE);
+    if (fnum1 == -1) {
+        printf("(3) open (2) of %s failed (%s)\n", fname, cli_errstr(&cli1));
+        return;
+    }
+
+    if (!cli_close(&cli1, fnum1)) {
+        printf("close2 failed (%s)\n", cli_errstr(&cli1));
+        return;
+    }
+
+	/* Ensure size == 0. */
+	if (!cli_getatr(&cli1, fname, NULL, &fsize, NULL)) {
+		printf("(3) getatr failed (%s)\n", cli_errstr(&cli1));
+		return;
+	}
+
+	if (fsize != 0) {
+		printf("(3) file size != 0\n");
+		return;
+	}
+    printf("finished open test 3\n");
+
 	cli_unlink(&cli1, fname);
 
     close_connection(&cli1);
 
-    printf("finished open test 2\n");
 }
 
 static void list_fn(file_info *finfo, const char *name, void *state)