diff --git a/lacomp.zsh b/lacomp.zsh
index e5e3ba6..d6bc31f 100755
--- a/lacomp.zsh
+++ b/lacomp.zsh
@@ -7,7 +7,7 @@ function ctime {
 }
 
 function mdate {
-	local dfmt="$(grep -m 1 -ioP '(?<=^Date\:\ ).*' ${fls[1]})"
+	local dfmt="$(grep -m 1 -oP '(?<=^[dD]ate\:\ ).*' $1)"
 	date '+%s' -d "$dfmt"
 }
 
@@ -16,19 +16,29 @@ while read LINE; do
 
 	unset cts
 	typeset -A cts
-	cts[${fls[1]}]=$(ctime "${fls[1]}")
-	cts[${fls[2]}]=$(ctime "${fls[2]}")
+	for i in $fls; do
+		cts[$i]=$(ctime "$i")
+	done
 
 	unset mds
 	typeset -A mds
-	mds[${fls[1]}]=$(mdate "${fls[1]}")
-	mds[${fls[2]}]=$(mdate "${fls[2]}")
+	for i in $fls; do
+		mds[$i]=$(mdate "$i")
+	done
 
-	if [ "${#cts}" -ne 2 ]; then
-		TMS=(${(nO)${(v)mds}})
-		echo "${(k)mds[(r)${TMS[1]}]}"
-	else
-		TMS=(${(nO)${(v)cts}})
-		echo "${(k)cts[(r)${TMS[1]}]}"
-	fi
+	while [ "${#fls}" -gt 1 ]; do
+		TMS=()
+		mf=""
+		if [ "${#mds}" -gt 1 ]; then
+			TMS=(${(nO)${(v)mds}})
+			mf="${(k)mds[(r)${TMS[1]}]}"
+			unset "mds[${(b)mf}]"
+		else
+			TMS=(${(nO)${(v)cts}})
+			mf="${(k)cts[(r)${TMS[1]}]}"
+			unset "cts[${(b)mf}]"
+		fi
+		fls=(${fls:#$mf})
+		echo "$mf"
+	done
 done
diff --git a/maildedupe.zsh b/maildedupe.zsh
index d08f58c..1976a6f 100755
--- a/maildedupe.zsh
+++ b/maildedupe.zsh
@@ -3,29 +3,43 @@
 fln=($@)
 
 flc=(${fln})
-fct="0"
+idc="0"
 typeset -A fls
 
 for i in $flc; do
+	id="$(grep -m 1 -oP '(?<=^[mM]essage-[iI][dD]\:\ \<).*(?=\>)' $i)"
 
-	fls[$i]=$(grep -m 1 -ioP '(?<=^Message-ID\:\ \<).*(?=\>)' "$i")
+	if [ ! -z "$id" ]; then
+		fls[$i]="$id"
 
-	fct=$(( ${fct} + 1 ))
-	printf '%.40s: %20s\r' 'Message-IDs collected' "${fct}/${#fln}" >&2
+		idc=$(( ${idc} + 1 ))
+		printf '%.40s: %20s\r' 'Message-IDs collected' "${idc}/${#fln}" >&2
+	fi
 done
 
-fct="0"
-for k1 v1 in ${(kv)fls}; do
-
-	for k2 v2 in ${(kv)fls}; do
-		if [[ "$v1" == "$v2" ]] && [[ "$k1" != "$k2" ]]; then
-			echo "$k1 $k2"
-			printf 'Message-ID duplicate: %s\n' "$v1" >&2
-		fi
-	done
-
-	fct=$(( ${fct} + 1 ))
-	unset "fls[$k1]"
-
-	printf '%.40s: %20s\r' 'Message-IDs compared' "${fct}/${#fln}" >&2
+printf '\n' >&2
+typeset -A idfcnt
+for v in $fls; do
+	idfcnt[$v]="$(( ${idfcnt[$v]:-0} + 1 ))"
 done
+
+fdc="0"
+for k v in ${(kv)idfcnt}; do
+	if [ "$v" -gt 1 ]; then
+		FL=()
+		while true; do
+			FN="${(k)fls[(r)$k]}"
+			if [ ! -z "$FN" ]; then
+				unset "fls[$FN]"
+				FL+=("$FN")
+			else
+				break
+			fi
+		done
+		printf '%s\n' "$FL"
+
+		fdc=$(( ${fdc} + ${#FL} ))
+		printf '%.40s: %20s\r' 'Message-ID duplicates' "${fdc}/${idc}" >&2
+	fi
+done
+[ "$fdc" -gt 0 ] && printf '\n' >&2