diff -ur openssh-5.3p1/Makefile.in openssh-5.3p1_atomic/Makefile.in
--- openssh-5.3p1/Makefile.in	2009-08-27 20:47:38.000000000 -0400
+++ openssh-5.3p1_atomic/Makefile.in	2009-11-20 09:31:03.000000000 -0500
@@ -141,8 +141,8 @@
 sshd$(EXEEXT): libssh.a	$(LIBCOMPAT) $(SSHDOBJS)
 	$(LD) -o $@ $(SSHDOBJS) $(LDFLAGS) -lssh -lopenbsd-compat $(SSHDLIBS) $(LIBS)
 
-scp$(EXEEXT): $(LIBCOMPAT) libssh.a scp.o progressmeter.o
-	$(LD) -o $@ scp.o progressmeter.o bufaux.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
+scp$(EXEEXT): $(LIBCOMPAT) libssh.a scp.o progressmeter.o entropy.o
+	$(LD) -o $@ scp.o progressmeter.o bufaux.o entropy.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
 
 ssh-add$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-add.o
 	$(LD) -o $@ ssh-add.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
@@ -159,8 +159,8 @@
 ssh-keyscan$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keyscan.o roaming_dummy.o
 	$(LD) -o $@ ssh-keyscan.o roaming_dummy.o $(LDFLAGS) -lssh -lopenbsd-compat -lssh $(LIBS)
 
-sftp-server$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-common.o sftp-server.o sftp-server-main.o
-	$(LD) -o $@ sftp-server.o sftp-common.o sftp-server-main.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
+sftp-server$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-common.o sftp-server.o sftp-server-main.o entropy.o
+	$(LD) -o $@ sftp-server.o sftp-common.o sftp-server-main.o entropy.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS)
 
 sftp$(EXEEXT): $(LIBCOMPAT) libssh.a sftp.o sftp-client.o sftp-common.o sftp-glob.o progressmeter.o
 	$(LD) -o $@ progressmeter.o sftp.o sftp-client.o sftp-common.o sftp-glob.o $(LDFLAGS) -lssh -lopenbsd-compat $(LIBS) $(LIBEDIT)
diff -ur openssh-5.3p1/scp.c openssh-5.3p1_atomic/scp.c
--- openssh-5.3p1/scp.c	2008-11-03 03:23:45.000000000 -0500
+++ openssh-5.3p1_atomic/scp.c	2009-11-20 09:31:03.000000000 -0500
@@ -143,6 +143,9 @@
 /* This is used to store the pid of ssh_program */
 pid_t do_cmd_pid = -1;
 
+/* temporary folder where the files will be storred before being moved to their actual location */
+char *tmpdir;
+
 static void
 killchild(int signo)
 {
@@ -395,6 +398,9 @@
 
 	if (!isatty(STDOUT_FILENO))
 		showprogress = 0;
+	
+	tmpdir=getenv("TMP");
+	if(!tmpdir)tmpdir="/tmp";
 
 	remin = STDIN_FILENO;
 	remout = STDOUT_FILENO;
@@ -868,7 +874,7 @@
 	mode_t mode, omode, mask;
 	off_t size, statbytes;
 	int setimes, targisdir, wrerrno = 0;
-	char ch, *cp, *np, *targ, *why, *vect[1], buf[2048];
+	char ch, *cp, *np, *targ, *why, *vect[1], buf[2048],*origname;
 	struct timeval tv[2];
 
 #define	atime	tv[0]
@@ -1024,6 +1030,12 @@
 		}
 		omode = mode;
 		mode |= S_IWRITE;
+
+		origname=np;
+                np=calloc(1,strlen(origname)+20);
+                sprintf(np,"%s.tmpscpparts.XXXXXX",origname);
+                mkstemp(np);
+
 		if ((ofd = open(np, O_WRONLY|O_CREAT, mode)) < 0) {
 bad:			run_err("%s: %s", np, strerror(errno));
 			continue;
@@ -1083,6 +1095,7 @@
 			run_err("%s: truncate: %s", np, strerror(errno));
 			wrerr = DISPLAYED;
 		}
+		
 		if (pflag) {
 			if (exists || omode != mode)
 #ifdef HAVE_FCHMOD
@@ -1109,6 +1122,16 @@
 		if (close(ofd) == -1) {
 			wrerr = YES;
 			wrerrno = errno;
+		}else{
+       		        if(rename(np,origname)){
+	                        wrerr = YES;
+                        	wrerrno = errno;
+               		}else{
+				xfree(np);
+				np=origname;
+				origname=0;
+			}
+
 		}
 		(void) response();
 		if (setimes && wrerr == NO) {
@@ -1129,6 +1152,10 @@
 		case DISPLAYED:
 			break;
 		}
+		if(origname){
+			xfree(np);
+			np=origname;
+		}
 	}
 screwup:
 	run_err("protocol error: %s", why);
diff -ur openssh-5.3p1/sftp-server.c openssh-5.3p1_atomic/sftp-server.c
--- openssh-5.3p1/sftp-server.c	2009-08-27 20:43:13.000000000 -0400
+++ openssh-5.3p1_atomic/sftp-server.c	2009-11-20 09:31:03.000000000 -0500
@@ -62,6 +62,8 @@
 /* Our client */
 struct passwd *pw = NULL;
 char *client_addr = NULL;
+char *origname = NULL;
+char *tmpdir = NULL;
 
 /* input and output queue */
 Buffer iqueue;
@@ -551,8 +553,18 @@
 	a = get_attrib();
 	flags = flags_from_portable(pflags);
 	mode = (a->flags & SSH2_FILEXFER_ATTR_PERMISSIONS) ? a->perm : 0666;
+	origname=NULL;
+	if (pflags & SSH2_FXF_WRITE || pflags & SSH2_FXF_CREAT){
+		origname=name;
+		name=calloc(1,11+strlen(tmpdir)+1);
+		sprintf(name,"%s/sftp_XXXXXX",tmpdir);
+		mkstemp(name);
+		logit("created tmp file for \"%s\": \"%s\"",origname,name);
+	}
+	
 	logit("open \"%s\" flags %s mode 0%o",
 	    name, string_from_portable(pflags), mode);
+	
 	fd = open(name, flags, mode);
 	if (fd < 0) {
 		status = errno_to_portable(errno);
@@ -575,13 +587,26 @@
 {
 	u_int32_t id;
 	int handle, ret, status = SSH2_FX_FAILURE;
-
+	char *name;
+	int namel;
 	id = get_int();
 	handle = get_handle();
 	debug3("request %u: close handle %u", id, handle);
 	handle_log_close(handle, NULL);
+	name=handle_to_name(handle);
+	namel=strlen(name);
+	name=calloc(1,namel+1);
+	memcpy(name,handle_to_name(handle),namel);
 	ret = handle_close(handle);
 	status = (ret == -1) ? errno_to_portable(errno) : SSH2_FX_OK;
+	if(origname!=NULL && status==SSH2_FX_OK){
+		if(rename(name,origname)){
+			logit("error moving file %s: %s",name,strerror(errno));
+			status = SSH2_FX_FAILURE;
+		}
+		xfree(origname);
+	}
+	xfree(name);
 	send_status(id, status);
 }
 
@@ -1341,7 +1366,7 @@
 	__progname = ssh_get_progname(argv[0]);
 	log_init(__progname, log_level, log_facility, log_stderr);
 
-	while (!skipargs && (ch = getopt(argc, argv, "f:l:che")) != -1) {
+	while (!skipargs && (ch = getopt(argc, argv, "f:l:t:che")) != -1) {
 		switch (ch) {
 		case 'c':
 			/*
@@ -1363,6 +1388,10 @@
 			if (log_facility == SYSLOG_FACILITY_NOT_SET)
 				error("Invalid log facility \"%s\"", optarg);
 			break;
+		case 't':
+			tmpdir=calloc(1,strlen(optarg)+1);
+			memcpy(tmpdir,optarg,strlen(optarg));
+			break;
 		case 'h':
 		default:
 			sftp_server_usage();
@@ -1370,6 +1399,12 @@
 	}
 
 	log_init(__progname, log_level, log_facility, log_stderr);
+	
+	if(tmpdir==NULL){
+                tmpdir=calloc(1,6),
+                strcpy(tmpdir,"/tmp/");
+        }
+	debug2("tmp dir: \"%s\"",tmpdir);
 
 	if ((cp = getenv("SSH_CONNECTION")) != NULL) {
 		client_addr = xstrdup(cp);