diff --git a/audio/celt051/README b/audio/celt051/README
new file mode 100644
index 0000000000..14d4fa85ce
--- /dev/null
+++ b/audio/celt051/README
@@ -0,0 +1,12 @@
+celt051 (low delay audio codec - version 0.5.1.x)
+
+CELT is a very low delay audio codec designed for high-quality
+communications. Traditional full-bandwidth  codecs such as Vorbis and
+AAC can offer high quality but they require codec delays of hundreds
+of milliseconds, which makes them unsuitable  for real-time
+interactive applications like teleconferencing. Speech targeted
+codecs, such as Speex or G.722, have lower 20-40ms delays but their
+speech focus and limited sampling rates restricts their quality,
+especially for music.
+
+celt051 is a parallel-installable (older) version of the celt codec.
diff --git a/audio/celt051/celt051.SlackBuild b/audio/celt051/celt051.SlackBuild
new file mode 100644
index 0000000000..28a286ac38
--- /dev/null
+++ b/audio/celt051/celt051.SlackBuild
@@ -0,0 +1,99 @@
+#!/bin/sh
+
+# Slackware build script for celt
+
+# Copyright 2010 Heinz Wiesinger, Amsterdam, The Netherlands
+# All rights reserved.
+#
+# Redistribution and use of this script, with or without modification, is
+# permitted provided that the following conditions are met:
+#
+# 1. Redistributions of this script must retain the above copyright
+#    notice, this list of conditions and the following disclaimer.
+#
+# THIS SOFTWARE IS PROVIDED BY THE AUTHOR ''AS IS'' AND ANY EXPRESS OR IMPLIED
+# WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+# MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO
+# EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+# PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
+# OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
+# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
+# OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
+# ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+
+# forked of celt slackbuild by ponce <matteo.bernardini@gmail.com>
+
+PRGNAM=celt051
+VERSION=0.5.1.3
+BUILD=${BUILD:-1}
+TAG=${TAG:-_SBo}
+
+# Automatically determine the architecture we're building on:
+if [ -z "$ARCH" ]; then
+  case "$( uname -m )" in
+    i?86) ARCH=i486 ;;
+    arm*) ARCH=arm ;;
+    # Unless $ARCH is already set, use uname -m for all other archs:
+       *) ARCH=$( uname -m ) ;;
+  esac
+fi
+
+CWD=$(pwd)
+TMP=${TMP:-/tmp/SBo}
+PKG=$TMP/package-$PRGNAM
+OUTPUT=${OUTPUT:-/tmp}
+
+if [ "$ARCH" = "i486" ]; then
+  SLKCFLAGS="-O2 -march=i486 -mtune=i686"
+  LIBDIRSUFFIX=""
+elif [ "$ARCH" = "i686" ]; then
+  SLKCFLAGS="-O2 -march=i686 -mtune=i686"
+  LIBDIRSUFFIX=""
+elif [ "$ARCH" = "x86_64" ]; then
+  SLKCFLAGS="-O2 -fPIC"
+  LIBDIRSUFFIX="64"
+else
+  SLKCFLAGS="-O2"
+  LIBDIRSUFFIX=""
+fi
+
+set -e
+
+rm -rf $PKG
+mkdir -p $TMP $PKG $OUTPUT
+cd $TMP
+rm -rf celt-$VERSION
+tar xvf $CWD/celt-$VERSION.tar.gz
+cd celt-$VERSION
+chown -R root:root .
+chmod -R u+w,go+r-w,a-s .
+
+CFLAGS="$SLKCFLAGS" \
+CXXFLAGS="$SLKCFLAGS" \
+./configure \
+  --prefix=/usr \
+  --libdir=/usr/lib${LIBDIRSUFFIX} \
+  --sysconfdir=/etc \
+  --localstatedir=/var \
+  --mandir=/usr/man \
+  --disable-static \
+  --build=$ARCH-slackware-linux \
+  --host=$ARCH-slackware-linux
+
+make
+make install-strip DESTDIR=$PKG
+
+find $PKG | xargs file | grep -e "executable" -e "shared object" | grep ELF \
+  | cut -f 1 -d : | xargs strip --strip-unneeded 2> /dev/null || true
+
+mkdir -p $PKG/usr/doc/$PRGNAM-$VERSION
+cp -a AUTHORS ChangeLog COPYING INSTALL NEWS README TODO \
+  $PKG/usr/doc/$PRGNAM-$VERSION
+cat $CWD/$PRGNAM.SlackBuild > $PKG/usr/doc/$PRGNAM-$VERSION/$PRGNAM.SlackBuild
+
+mkdir -p $PKG/install
+cat $CWD/slack-desc > $PKG/install/slack-desc
+
+cd $PKG
+/sbin/makepkg -l y -c n $OUTPUT/$PRGNAM-$VERSION-$ARCH-$BUILD$TAG.${PKGTYPE:-tgz}
diff --git a/audio/celt051/celt051.info b/audio/celt051/celt051.info
new file mode 100644
index 0000000000..249b8d0573
--- /dev/null
+++ b/audio/celt051/celt051.info
@@ -0,0 +1,10 @@
+PRGNAM="celt051"
+VERSION="0.5.1.3"
+HOMEPAGE="http://www.celt-codec.org/"
+DOWNLOAD="http://downloads.xiph.org/releases/celt/celt-0.5.1.3.tar.gz"
+MD5SUM="67e7b5e45db57a6f1f0a6962f5ecb190"
+DOWNLOAD_x86_64=""
+MD5SUM_x86_64=""
+MAINTAINER="ponce"
+EMAIL="matteo.bernardini@gmail.com"
+APPROVED="rworkman"
diff --git a/audio/celt051/slack-desc b/audio/celt051/slack-desc
new file mode 100644
index 0000000000..17f91dedbe
--- /dev/null
+++ b/audio/celt051/slack-desc
@@ -0,0 +1,19 @@
+# HOW TO EDIT THIS FILE:
+# The "handy ruler" below makes it easier to edit a package description.  Line
+# up the first '|' above the ':' following the base package name, and the '|'
+# on the right side marks the last column you can put a character in.  You must
+# make exactly 11 lines for the formatting to be correct.  It's also
+# customary to leave one space after the ':'.
+
+       |-----handy-ruler------------------------------------------------------|
+celt051: celt051 (low delay audio codec - version 0.5.1.x)
+celt051:
+celt051: CELT is a very low delay audio codec designed for high-quality
+celt051: communications. Traditional full-bandwidth codecs such as Vorbis and
+celt051: AAC can offer high quality but they require codec delays of hundreds
+celt051: of milliseconds, which makes them unsuitable for real-time
+celt051: interactive applications like teleconferencing.  Speech targeted
+celt051: codecs, such as Speex or G.722, have lower 20-40ms delays but their
+celt051: speech focus and limited sampling rates restricts their quality,
+celt051: especially for music.
+celt051: