LC_ALL=C TZ=UTC0 diff -Naur ucarp-1.5.1-1ubuntu0/etc/network/if-up.d/ucarp ucarp-mine/etc/network/if-up.d/ucarp
--- ucarp-1.5.1-1ubuntu0/etc/network/if-up.d/ucarp      2012-04-03 17:47:18.689999403 +0000
+++ ucarp-mine/etc/network/if-up.d/ucarp        2012-04-03 17:52:07.290013272 +0000
@@ -33,6 +33,12 @@
     EXTRA_PARAMS="$EXTRA_PARAMS -r $IF_UCARP_DEADRATIO"
 fi

+if [ -n "$IF_UCARP_NEUTRAL" ]; then
+    if ! expr "$IF_UCARP_NEUTRAL" : "no\|off\|false\|0" > /dev/null; then
+        EXTRA_PARAMS="$EXTRA_PARAMS -n"
+    fi
+fi
+
 if [ -n "$IF_UCARP_NOMCAST" ]; then
     if ! expr "$IF_UCARP_NOMCAST" : "no\|off\|false\|0" > /dev/null; then
         EXTRA_PARAMS="$EXTRA_PARAMS -M"