diff -Nru casper-1.307/bin/casper-set-selections casper-1.308/bin/casper-set-selections
--- casper-1.307/bin/casper-set-selections	2012-03-01 02:47:59.000000000 +0000
+++ casper-1.308/bin/casper-set-selections	2012-03-13 09:32:37.000000000 +0000
@@ -51,6 +51,7 @@
 		line="$multiline $line"
 		multiline=""
 	fi
+	echo "$line" >>/tmp/casper-preseed.log
 	
 	package=""
 	var=""
diff -Nru casper-1.307/debian/changelog casper-1.308/debian/changelog
--- casper-1.307/debian/changelog	2012-03-09 16:57:45.000000000 +0000
+++ casper-1.308/debian/changelog	2012-03-13 10:33:27.000000000 +0000
@@ -1,3 +1,10 @@
+casper (1.308) precise; urgency=low
+
+  * Reconfigure jackd2 if jackd/tweak_rt_limits has been preseeded
+    (LP: #923810).
+
+ -- Colin Watson <cjwatson@ubuntu.com>  Tue, 13 Mar 2012 10:33:24 +0000
+
 casper (1.307) precise; urgency=low
 
   * Add 50ubiquity-bluetooth-agent to detect ubiquity-bluetooth-agent and
diff -Nru casper-1.307/scripts/casper-bottom/45jackd2 casper-1.308/scripts/casper-bottom/45jackd2
--- casper-1.307/scripts/casper-bottom/45jackd2	1970-01-01 00:00:00.000000000 +0000
+++ casper-1.308/scripts/casper-bottom/45jackd2	2012-03-13 09:34:17.000000000 +0000
@@ -0,0 +1,33 @@
+#!/bin/sh
+
+PREREQ=""
+DESCRIPTION="Configuring jackd2..."
+
+prereqs()
+{
+	echo "$PREREQ"
+}
+
+case $1 in
+# get pre-requisites
+prereqs)
+       prereqs
+       exit 0
+       ;;
+esac
+
+. /scripts/casper-functions
+
+log_begin_msg "$DESCRIPTION"
+
+if fgrep -qs jackd/tweak_rt_limits /tmp/casper-preseed.log; then
+	# So far this has only been set in casper's environment.  Copy it
+	# over to the master files early so that dpkg-reconfigure in /root
+	# can see it.
+	fgrep jackd/tweak_rt_limits /tmp/casper-preseed.log | \
+		chroot /root debconf-set-selections
+
+	casper-reconfigure /root jackd2
+fi
+
+log_end_msg
diff -Nru casper-1.307/ubiquity-hooks/45jackd2 casper-1.308/ubiquity-hooks/45jackd2
--- casper-1.307/ubiquity-hooks/45jackd2	1970-01-01 00:00:00.000000000 +0000
+++ casper-1.308/ubiquity-hooks/45jackd2	2012-03-13 10:32:13.000000000 +0000
@@ -0,0 +1,18 @@
+#!/bin/sh
+set -e
+
+. /usr/share/debconf/confmodule
+
+if db_get jackd/tweak_rt_limits; then
+	# Using DEBCONF_DB_REPLACE is a hack to force configdb to be
+	# read-only, which debconf-copydb doesn't currently arrange for
+	# itself.
+	DEBCONF_DB_REPLACE=configdb debconf-copydb configdb targetdb \
+		-p jackd/tweak_rt_limits \
+		--config=Name:targetdb --config=Driver:File \
+		--config=Mode:0644 \
+		--config=Filename:/target/var/cache/debconf/config.dat
+	casper-reconfigure /target jackd2
+fi
+
+exit 0