diff -ur amanda-2.6.1p1/changer-src/chg-zd-mtx.sh amanda-2.6.1p1-sh/changer-src/chg-zd-mtx.sh
--- amanda-2.6.1p1/changer-src/chg-zd-mtx.sh	2008-12-16 21:46:41.000000000 +0100
+++ amanda-2.6.1p1-sh/changer-src/chg-zd-mtx.sh	2009-07-03 21:00:25.379617588 +0200
@@ -364,7 +364,7 @@
 
 internal_call=0
 Exit() {
-	if [ $internal_call -gt 0 ]; then
+	if [ "$internal_call" -gt 0 ]; then
 		call_type=Return
 	else
 		call_type=Exit
@@ -376,7 +376,7 @@
 	exit_answer="$@"
 	Log $call_type "($code) -> $exit_slot $@"
 	echo "$exit_slot" "$@"
-	if [ $call_type = Return ]; then
+	if [ "$call_type" = "Return" ]; then
 		return $code
 	fi
 	amgetconf dbclose.$myname:$DBGFILE > /dev/null 2>&1
@@ -393,12 +393,12 @@
 	"$@" > $stdout 2> $stderr
 	exitcode=$?
 	Log `_ 'Exit code: %s' "$exitcode"`
-	if [ -s $stdout ]
+	if [ -s "$stdout" ]
 	then
 		LogAppend Stdout:
 		cat $stdout >> $DBGFILE
 	fi
-	if [ -s $stderr ]
+	if [ -s "$stderr" ]
 	then
 		LogAppend Stderr:
 		cat $stderr >> $DBGFILE
@@ -425,13 +425,13 @@
 mtx_status_valid=0
 get_mtx_status() {
 	test -n "$DEBUG" && set -x
-	if [ $mtx_status_valid -ne 0 ]; then
+	if [ "$mtx_status_valid" -ne 0 ]; then
 		return 0
 	fi
 	rm -f $mtx_status
 	Run $MTX status > $mtx_status 2>&1
 	status=$?
-	if [ $status -eq 0 ]; then
+	if [ "$status" -eq 0 ]; then
 		mtx_status_valid=1
 	fi
 
@@ -503,7 +503,7 @@
 	fi
 
 	#Use the current slot if it's empty and we don't know which slot is loaded'
-	if [ $loadedslot -eq -2 ]; then
+	if [ "$loadedslot" -eq -2 ]; then
 		set x `sed -n '
 {
     /^.*Storage Element '$currentslot':Empty/ {
@@ -526,13 +526,13 @@
 ' < $mtx_status 2>& 1`
 		shift				# get rid of the "x"
 		loadedslotx=$1
-		if [ ! -z $loadedslotx ]; then
+		if [ ! -z "$loadedslotx" ]; then
 			loadedslot=$loadedslotx
 		fi
 	fi
 
 	#Use the first empty slot if we don't know which slot is loaded'
-	if [ $loadedslot -eq -2 ]; then
+	if [ "$loadedslot" -eq -2 ]; then
 		set x `sed -n '
 {
     /^.*Storage Element \([0-9][0-9]*\):Empty/ {
@@ -606,27 +606,27 @@
 }
 ' < $mtx_status 2>&1 | grep -v "^${cleanslot}\$" | sort -n`
 	slot_list=`echo $slot_list`		# remove the newlines
-	if [ $firstslot -lt 0 -o $lastslot -lt 0 ]; then
+	if [ "$firstslot" -lt 0 -o "$lastslot" -lt 0 ]; then
 		last=$lastslot
 		for slot in $slot_list; do
-			if [ $firstslot -lt 0 ]; then
+			if [ "$firstslot" -lt 0 ]; then
 				Log `_ 'SLOTLIST -> firstslot set to %s' "$slot"`
 				firstslot=$slot
 			fi
-			if [ $lastslot -lt 0 ]; then
+			if [ "$lastslot" -lt 0 ]; then
 				last=$slot
 			fi
 		done
-		if [ $lastslot -lt 0 -a $last -ge 0 ]; then
+		if [ "$lastslot" -lt 0 -a "$last" -ge 0 ]; then
 			Log `_ 'SLOTLIST -> lastslot set to %s' "$last"`
 			lastslot=$last
 		fi
-		if [ $firstslot -lt 0 ]; then
+		if [ "$firstslot" -lt 0 ]; then
 			Exit 2 \
 			     `_ '<none>'` \
 			     `_ 'cannot determine first slot'`
 			return $?		# in case we are internal
-		elif [ $lastslot -lt 0 ]; then
+		elif [ "$lastslot" -lt 0 ]; then
 			Exit 2 \
 			     `_ '<none>'` \
 			     `_ 'cannot determine last slot'`
@@ -635,7 +635,7 @@
 	fi
 	amanda_slot_list=
 	for slot in $slot_list; do
-		if [ $slot -ge $firstslot -a $slot -le $lastslot ]; then
+		if [ "$slot" -ge "$firstslot" -a "$slot" -le "$lastslot" ]; then
 			amanda_slot_list="$amanda_slot_list $slot"
 		fi
 	done
@@ -671,7 +671,7 @@
 			     `_ 'Line %s malformed in %s: %s %s %s' "$line" "$labelfile" "$lbl" "$bc" "$junk"`
 			return $?		# in case we are internal
 		fi
-		if [ $lbl = "$lbl_search" -o $bc = "$bc_search" ]; then
+		if [ "$lbl" = "$lbl_search" -o "$bc" = "$bc_search" ]; then
 			if [ $labelfile_entry_found -ne 0 ]; then
 				Log       `_ 'ERROR    -> Duplicate entries: %s line %s' "$labelfile" "$line"`
 				LogAppend `_ '         -> Remove %s and run "%s %s update"' "$labelfile" "$sbindir/amtape" "$config"`
@@ -860,7 +860,7 @@
         Exit 2 \
              ` _ '<none>'` \
              "tapedev $rawtape is not a tape device."
-elif [ $tape = "/dev/null" -o `expr "$tape" : 'null:'` -eq 5 ]; then
+elif [ "$tape" = "/dev/null" -o "`expr "$tape" : 'null:'`" -eq 5 ]; then
 	Exit 2 \
 	     `_ '<none>'` \
 	     "tapedev ($tape) may not be the null device"
@@ -871,7 +871,7 @@
 	Exit 2 \
 	     `_ '<none>'` \
 	     "changerdev may not be empty"
-elif [ $TAPE = "/dev/null" ]; then
+elif [ "$TAPE" = "/dev/null" ]; then
 	Exit 2 \
 	     `_ '<none>'` \
 	     "changerdev ($TAPE) may not be the null device"
@@ -884,19 +884,19 @@
 #### Set up the various config files.
 
 conf_match=`expr "$changerfile" : .\*\.conf\$`
-if [ $conf_match -ge 6 ]; then
+if [ "$conf_match" -ge 6 ]; then
 	configfile=$changerfile
 	changerfile=`echo $changerfile | sed 's/.conf$//g'`
 else
 	configfile=$changerfile.conf
 fi
 
-if [ ! -e $configfile ]; then
+if [ ! -e "$configfile" ]; then
 	Exit 2 \
 	     `_ '<none>'` \
 	     "configuration file \"$configfile\" doesn't exist"
 fi
-if [ ! -f $configfile ]; then
+if [ ! -f "$configfile" ]; then
 	Exit 2 \
 	     `_ '<none>'` \
 	     "configuration file \"$configfile\" is not a file"
@@ -907,10 +907,10 @@
 slotfile=$changerfile-slot
 labelfile=$changerfile-barcodes
 slotinfofile=""
-[ ! -s $cleanfile ] && echo 0 > $cleanfile
-[ ! -s $accessfile ] && echo 0 > $accessfile
-[ ! -s $slotfile ] && echo -1 > $slotfile
-[ ! -f $labelfile ] && > $labelfile
+[ ! -s "$cleanfile" ] && echo 0 > $cleanfile
+[ ! -s "$accessfile" ] && echo 0 > $accessfile
+[ ! -s "$slotfile" ] && echo -1 > $slotfile
+[ ! -f "$labelfile" ] && > $labelfile
 cleancount=`cat $cleanfile`
 accesscount=`cat $accessfile`
 
@@ -957,7 +957,7 @@
 
 # Get DBGFILE set if it is not already.
 
-if [ $DBGFILE = /dev/null ]; then
+if [ "$DBGFILE" = /dev/null ]; then
 	if [ -d "$DBGDIR" ]; then
 		DBGFILE=$DBGDIR/changer.debug.drive$driveslot
 	else
@@ -1037,9 +1037,9 @@
 
 Log `_ "Config info:"`
 for var in $varlist; do
-	if [ $var = "OFFLINE_BEFORE_UNLOAD" ]; then
+	if [ "$var" = "OFFLINE_BEFORE_UNLOAD" ]; then
 		continue			# old name
-	elif [ $var = "AUTOCLEAN" ]; then
+	elif [ "$var" = "AUTOCLEAN" ]; then
 		continue			# old name
 	elif [ $var = "slotinfofile" ]; then
 		continue			# not numeric
@@ -1062,12 +1062,12 @@
 
 # Run the rest of the config file sanity checks.
 
-if [ $firstslot -gt $lastslot ]; then
+if [ "$firstslot" -gt "$lastslot" ]; then
 	Exit 2 \
 	     `_ '<none>'` \
 	     `_ 'firstslot (%s) greater than lastslot (%s) in %s' "$firstslot" "$lastslot" "$configfile"`
 fi
-if [ $autoclean -ne 0 -a $cleanslot -lt 0 ]; then
+if [ "$autoclean" -ne 0 -a "$cleanslot" -lt 0 ]; then
 	Exit 2 \
 	     `_ '<none>'` \
 	     `_ 'autoclean set but cleanslot not valid (%s)' "$cleanslot"`
@@ -1077,10 +1077,10 @@
 
 currentslot=`cat $slotfile`
 if IsNumeric "$currentslot" ; then
-	if [ $currentslot -lt $firstslot ]; then
+	if [ "$currentslot" -lt "$firstslot" ]; then
 		Log `_ 'SETUP    -> current slot %s less than %s ... resetting to %s' "$currentslot" "$firstslot" "$firstslot"`
 		currentslot=$firstslot
-	elif [ $currentslot -gt $lastslot ]; then
+	elif [ "$currentslot" -gt "$lastslot" ]; then
 		Log `_ 'SETUP    -> current slot %s greater than %s ... resetting to %s' "$currentslot" "$lastslot" "$lastslot"`
 		currentslot=$lastslot
 	fi
@@ -1093,19 +1093,19 @@
 first_slot_in_list=-1
 next_slot_after_current=-1
 for slot in $slot_list; do
-	if [ $first_slot_in_list -lt 0 ]; then
+	if [ "$first_slot_in_list" -lt 0 ]; then
 		first_slot_in_list=$slot	# in case $firstslot is missing
 	fi
-	if [ $slot -eq $currentslot ]; then
+	if [ "$slot" -eq "$currentslot" ]; then
 		found_current=1
 		break
-	elif [ $slot -gt $currentslot ]; then
+	elif [ "$slot" -gt "$currentslot" ]; then
 		next_slot_after_current=$slot	# $currentslot is missing
 		break
 	fi
 done
-if [ $found_current -eq 0 ]; then
-	if [ $next_slot_after_current -lt 0 ]; then
+if [ "$found_current" -eq 0 ]; then
+	if [ "$next_slot_after_current" -lt 0 ]; then
 		new_currentslot=$first_slot_in_list
 	else
 		new_currentslot=$next_slot_after_current
@@ -1124,9 +1124,9 @@
 	test -n "$DEBUG" && set -x
 	Log `_ 'EJECT    -> ejecting tape from %s' "$tape"`
 	get_loaded_info 
-	if [ $loadedslot -gt 0 ]; then
+	if [ "$loadedslot" -gt 0 ]; then
 		Log `_ 'EJECT    -> moving tape from drive %s to storage slot %s' "$driveslot" "$loadedslot"`
-		if [ $offline_before_unload -ne 0 ]; then
+		if [ "$offline_before_unload" -ne 0 ]; then
                         Run try_eject_device $tape
 		fi
 		sleep $unloadpause
@@ -1134,7 +1134,7 @@
 		status=$?
 		Log `_ '         -> status %s, result "%s"' "$status" "$result"`
 		mtx_status_valid=0
-		if [ $status -ne 0 ]; then
+		if [ "$status" -ne 0 ]; then
 			answer="$result"
 			code=2
 		else
@@ -1213,7 +1213,7 @@
 	prev_slot=$1
 	shift
 	while [ $# -gt 0 ]; do
-		if [ $1 -eq $find_slot ]; then
+		if [ "$1" -eq "$find_slot" ]; then
 			break
 		fi
 		prev_slot=$1
@@ -1242,15 +1242,15 @@
 	# If the desired slot is already loaded, we are done.  Only update
 	# current slot if this is not the cleaning slot.
 	get_loaded_info
-	if [ $loadslot = $loadedslot ]; then
-		if [ $loadslot -ne $cleanslot ]; then
+	if [ "$loadslot" = "$loadedslot" ]; then
+		if [ "$loadslot" -ne "$cleanslot" ]; then
 			rm -f $slotfile
 			echo $loadslot > $slotfile
 		fi
 		Exit 0 "$loadedslot" "$rawtape"
 		return $?			# in case we are internal
 	fi
-	if [ $loadedslot -eq -2 ]; then
+	if [ "$loadedslot" -eq -2 ]; then
 		Exit 0 "$loadedslot" "$rawtape"
 		return $?			# in case we are internal
         fi
@@ -1258,20 +1258,20 @@
 	# If we are loading the cleaning tape, bump the cleaning count
 	# and reset the access count.  Otherwise, bump the access count
 	# and see if it is time to do a cleaning.
-	if [ $loadslot = $cleanslot ]; then
+	if [ "$loadslot" = "$cleanslot" ]; then
 		rm -f $cleanfile $accessfile
 		expr $cleancount + 1 > $cleanfile
 		echo 0 > $accessfile
 	else
 		rm -f $accessfile
 		expr $accesscount + 1 > $accessfile
-		if [ $autoclean -ne 0 -a $accesscount -gt $autocleancount ]
+		if [ "$autoclean" -ne 0 -a "$accesscount" -gt "$autocleancount" ]
 		then
 			internal_call=`expr $internal_call + 1`
 			loadslot clean > /dev/null 2>&1
 			status=$?
 			internal_call=`expr $internal_call - 1`
-			if [ $status -ne 0 ]; then
+			if [ "$status" -ne 0 ]; then
 				Exit $status "$loadslot" "$exit_answer"
 				return $?	# in case we are internal
 			fi
@@ -1291,14 +1291,14 @@
 	eject > /dev/null 2>&1
 	status=$?
 	internal_call=`expr $internal_call - 1`
-	if [ $status -gt 1 ]; then
+	if [ "$status" -gt 1 ]; then
 		Exit $status "$exit_slot" "$exit_answer"
 		return $?			# in case we are internal
 	fi
 
 	# If we were doing an "advance", we are done.
-	if [ $whichslot = advance ]; then
-		if [ $loadslot -ne $cleanslot ]; then
+	if [ "$whichslot" = "advance" ]; then
+		if [ "$loadslot" -ne "$cleanslot" ]; then
 			rm -f $slotfile
 			echo $loadslot > $slotfile
 		fi
@@ -1312,7 +1312,7 @@
 	status=$?
 	Log `_ '         -> status %s, result "%s"' "$status" "$result"`
 	mtx_status_valid=0
-	if [ $status -ne 0 ]; then
+	if [ "$status" -ne 0 ]; then
 		Exit 2 "$loadslot" "$result"
 		return $?			# in case we are internal
 	fi
@@ -1322,7 +1322,7 @@
 	# for "long enough" (as determined empirically by the user),
 	# then return success.
 	###
-	if [ $loadslot -eq $cleanslot ]; then
+	if [ "$loadslot" -eq "$cleanslot" ]; then
 		Run sleep $cleancycle
 		Exit 0 "$loadslot" "$rawtape"
 		return $?			# in case we are internal
@@ -1334,7 +1334,7 @@
 	waittime=0
 	ready=0
 	sleep $initial_poll_delay
-	while [ $waittime -lt $max_drive_wait ]; do
+	while [ "$waittime" -lt "$max_drive_wait" ]; do
                 amdevcheck_status $tape
 		if [ $? -eq 0 ]; then
 			ready=1
@@ -1343,12 +1343,12 @@
 		sleep $poll_drive_ready
 		waittime=`expr $waittime + $poll_drive_ready`
 	done
-	if [ $ready -eq 0 ]; then
+	if [ "$ready" -eq 0 ]; then
 		Exit 2 "$loadslot" `_ 'Drive not ready after %s seconds: %s' "$max_drive_wait" "$amdevcheck_message"`
 		return $?			# in case we are internal
 	fi
 
-	if [ $loadslot -ne $cleanslot ]; then
+	if [ "$loadslot" -ne "$cleanslot" ]; then
 		rm -f $slotfile
 		echo $loadslot > $slotfile
 	fi
@@ -1379,11 +1379,11 @@
 	# can search based on barcodes.
 	###
 	reader=
-        if [ $havereader -eq 1 ]; then
+        if [ "$havereader" -eq 1 ]; then
 		reader=1
         fi
 
-	if [ $currentslot -lt $firstslot -o $currentslot -gt $lastslot ]; then
+	if [ "$currentslot" -lt "$firstslot" -o "$currentslot" -gt "$lastslot" ]; then
 		currentslot=$firstslot		# what "current" will get
 	fi
 	numslots=`expr $lastslot - $firstslot + 1`
@@ -1404,12 +1404,12 @@
 	fi
         tapelabel=$1
         get_loaded_info
-	if [ $loadedslot -lt 0 ]; then
+	if [ "$loadedslot" -lt 0 ]; then
 		Exit 1 `_ '<none>'` `_ 'No tape currently loaded'`
 		return $?			# in case we are internal
 	fi
 	record_label_in_slot "$tapelabel" "$loadedslot"
-	if [ $havereader -eq 0 ]; then
+	if [ "$havereader" -eq 0 ]; then
 		Exit 0 "$loadedslot" "$rawtape"	# that's all we needed
 		return $?			# in case we are internal
 	fi
@@ -1419,7 +1419,7 @@
 	fi
 	Log       `_ 'LABEL    -> Adding label "%s" with barcode "%s" for slot %s into %s' "$tapelabel" "$loadedbarcode" "$loadedslot" "$labelfile"`
 	read_labelfile "$tapelabel" "$loadedbarcode" < $labelfile
-	if [ $labelfile_entry_found -ne 0 ]; then
+	if [ "$labelfile_entry_found" -ne 0 ]; then
 		lf_val=
 		if [ "$labelfile_barcode" != "$loadedbarcode" ]; then
 			lf_type=label
@@ -1465,13 +1465,13 @@
 		return $?			# in case we are internal
 	fi
         tapelabel=$1
-	if [ $havereader -eq 0 ]; then
+	if [ "$havereader" -eq 0 ]; then
 		Exit 2 `_ '<none>'` `_ 'Not configured with barcode reader'`
 		return $?			# in case we are internal
 	fi
 	Log `_ 'SEARCH   -> Hunting for label "%s"' "$tapelabel"`
 	read_labelfile "$tapelabel" "" < $labelfile
-	if [ $labelfile_entry_found -eq 0 ]; then
+	if [ "$labelfile_entry_found" -eq 0 ]; then
 		LogAppend `_ '         -> !!! label "%s" not found in %s !!!' "$tapelabel" "$labelfile"`
 		LogAppend `_ '         -> Remove %s and run "%s %s update"' "$labelfile" "$sbindir/amtape" "$config"`
 		Exit 2 \