diff --git a/desktop/slock/README b/desktop/slock/README
index 7170cbcb86..6ede76c89e 100644
--- a/desktop/slock/README
+++ b/desktop/slock/README
@@ -1 +1,7 @@
 slock is a simple X display locker.
+
+Build with FAILCOLOR=yes to support upstream failcolor patch:
+http://tools.suckless.org/slock/patches/failcolor
+
+Build with OVERRIDEXFLOCK4=yes to add slock symlink to:
+/usr/local/bin/xflock4
diff --git a/desktop/slock/doinst.sh b/desktop/slock/doinst.sh
new file mode 100644
index 0000000000..3f9d5d235c
--- /dev/null
+++ b/desktop/slock/doinst.sh
@@ -0,0 +1,3 @@
+# Override xflock4 binary
+( cd usr/local/bin ; rm -rf xflock4 )
+( cd usr/local/bin ; ln -sf /usr/bin/slock xflock4 )
diff --git a/desktop/slock/slock-1.2-failcolor.diff b/desktop/slock/slock-1.2-failcolor.diff
new file mode 100644
index 0000000000..3b2a03193f
--- /dev/null
+++ b/desktop/slock/slock-1.2-failcolor.diff
@@ -0,0 +1,62 @@
+diff --git a/config.def.h b/config.def.h
+index 89e5977..7f55466 100644
+--- a/config.def.h
++++ b/config.def.h
+@@ -1,2 +1,3 @@
+ #define COLOR1 "black"
+ #define COLOR2 "#005577"
++#define COLOR3 "#550000"
+diff --git a/slock.c b/slock.c
+index face75e..8519ce2 100644
+--- a/slock.c
++++ b/slock.c
+@@ -29,12 +29,13 @@ typedef struct {
+ 	int screen;
+ 	Window root, win;
+ 	Pixmap pmap;
+-	unsigned long colors[2];
++	unsigned long colors[3];
+ } Lock;
+ 
+ static Lock **locks;
+ static int nscreens;
+ static Bool running = True;
++static Bool tried = False;
+ 
+ static void
+ die(const char *errstr, ...) {
+@@ -135,6 +136,7 @@ readpw(Display *dpy, const char *pws)
+ #ifdef HAVE_BSD_AUTH
+ 				running = !auth_userokay(getlogin(), NULL, "auth-xlock", passwd);
+ #else
++				tried=True;
+ 				running = !!strcmp(crypt(passwd, pws), pws);
+ #endif
+ 				if(running)
+@@ -162,7 +164,7 @@ readpw(Display *dpy, const char *pws)
+ 				}
+ 			} else if(llen != 0 && len == 0) {
+ 				for(screen = 0; screen < nscreens; screen++) {
+-					XSetWindowBackground(dpy, locks[screen]->win, locks[screen]->colors[0]);
++					XSetWindowBackground(dpy, locks[screen]->win, locks[screen]->colors[tried ? 2 : 0]);
+ 					XClearWindow(dpy, locks[screen]->win);
+ 				}
+ 			}
+@@ -179,7 +181,7 @@ unlockscreen(Display *dpy, Lock *lock) {
+ 		return;
+ 
+ 	XUngrabPointer(dpy, CurrentTime);
+-	XFreeColors(dpy, DefaultColormap(dpy, lock->screen), lock->colors, 2, 0);
++	XFreeColors(dpy, DefaultColormap(dpy, lock->screen), lock->colors, 3, 0);
+ 	XFreePixmap(dpy, lock->pmap);
+ 	XDestroyWindow(dpy, lock->win);
+ 
+@@ -212,6 +214,8 @@ lockscreen(Display *dpy, int screen) {
+ 	lock->win = XCreateWindow(dpy, lock->root, 0, 0, DisplayWidth(dpy, lock->screen), DisplayHeight(dpy, lock->screen),
+ 			0, DefaultDepth(dpy, lock->screen), CopyFromParent,
+ 			DefaultVisual(dpy, lock->screen), CWOverrideRedirect | CWBackPixel, &wa);
++	XAllocNamedColor(dpy, DefaultColormap(dpy, lock->screen), COLOR3, &color, &dummy);
++	lock->colors[2] = color.pixel;
+ 	XAllocNamedColor(dpy, DefaultColormap(dpy, lock->screen), COLOR2, &color, &dummy);
+ 	lock->colors[1] = color.pixel;
+ 	XAllocNamedColor(dpy, DefaultColormap(dpy, lock->screen), COLOR1, &color, &dummy);
diff --git a/desktop/slock/slock.SlackBuild b/desktop/slock/slock.SlackBuild
index e3e232f5a1..0b51ea5f65 100644
--- a/desktop/slock/slock.SlackBuild
+++ b/desktop/slock/slock.SlackBuild
@@ -20,6 +20,8 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 # THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+# Modified by Mario Preksavec <mario@slackware.hr>
+
 PRGNAM=slock
 VERSION=${VERSION:-1.2}
 BUILD=${BUILD:-2}
@@ -69,6 +71,12 @@ find -L . \
  \( -perm 666 -o -perm 664 -o -perm 600 -o -perm 444 -o -perm 440 -o -perm 400 \) \
  -exec chmod 644 {} \;
 
+# Support upstream failcolor patch
+# http://tools.suckless.org/slock/patches/failcolor
+if [ "${FAILCOLOR:-no}" != "no" ]; then
+  patch -p1 <$CWD/slock-1.2-failcolor.diff
+fi
+
 # This uses our CFLAGS defined above
 sed "s/@SLACKCFLAGS@/$SLKCFLAGS/" $CWD/config.mk.patch | patch -p1
 
@@ -91,5 +99,10 @@ cat $CWD/$PRGNAM.SlackBuild > $PKG/usr/doc/$PRGNAM-$VERSION/$PRGNAM.SlackBuild
 mkdir -p $PKG/install
 cat $CWD/slack-desc > $PKG/install/slack-desc
 
+# User knows whats at stake
+if [ "${OVERRIDEXFLOCK4:-no}" != "no" ]; then
+  cat $CWD/doinst.sh > $PKG/install/doinst.sh
+fi
+
 cd $PKG
 /sbin/makepkg -l y -c n $OUTPUT/$PRGNAM-$VERSION-$ARCH-$BUILD$TAG.${PKGTYPE:-tgz}