diff -Nur netqmail-1.05/netqmail-1.05/qmail-pop3d.c netqmail-1.05-fix/netqmail-1.05/qmail-pop3d.c
--- netqmail-1.05/netqmail-1.05/qmail-pop3d.c	2006-11-20 11:45:13.000000000 +0100
+++ netqmail-1.05-fix/netqmail-1.05/qmail-pop3d.c	2006-11-20 11:45:57.000000000 +0100
@@ -114,6 +114,7 @@
 
 struct message {
   int flagdeleted;
+  int flagseen;
   unsigned long size;
   char *fn;
 } *m;
@@ -139,6 +140,7 @@
     prioq_delmin(&pq);
     m[i].fn = filenames.s + pe.id;
     m[i].flagdeleted = 0;
+    m[i].flagseen = 0;
     if (stat(m[i].fn,&st) == -1)
       m[i].size = 0;
     else
@@ -164,7 +166,10 @@
 void pop3_rset(arg) char *arg;
 {
   int i;
-  for (i = 0;i < numm;++i) m[i].flagdeleted = 0;
+  for (i = 0;i < numm;++i) {
+    m[i].flagdeleted = 0;
+    m[i].flagseen = 0;
+  }
   last = 0;
   okay(0);
 }
@@ -180,18 +185,33 @@
 void pop3_quit(arg) char *arg;
 {
   int i;
+  char *dt;
+  
   for (i = 0;i < numm;++i)
     if (m[i].flagdeleted) {
       if (unlink(m[i].fn) == -1) err_nounlink();
     }
-    else
+    else {
       if (str_start(m[i].fn,"new/")) {
 	if (!stralloc_copys(&line,"cur/")) die_nomem();
 	if (!stralloc_cats(&line,m[i].fn + 4)) die_nomem();
-	if (!stralloc_cats(&line,":2,")) die_nomem();
+	if (m[i].flagseen == 0) {
+          if (!stralloc_cats(&line,":2,")) die_nomem();
+        } else {
+          if (!stralloc_cats(&line,":2,S")) die_nomem();
+        }
 	if (!stralloc_0(&line)) die_nomem();
 	rename(m[i].fn,line.s); /* if it fails, bummer */
+      } else {
+        dt = m[i].fn + str_rchr(m[i].fn, ':');
+        if (m[i].flagseen == 1 && (*(dt + str_chr(dt, 'S')) != 'S')) {
+          if (!stralloc_copys(&line,m[i].fn)) die_nomem();
+          if (!stralloc_cats(&line,"S")) die_nomem();
+          if (!stralloc_0(&line)) die_nomem();
+          rename(m[i].fn,line.s);
+        }
       }
+    }
   okay(0);
   die();
 }
@@ -271,6 +291,7 @@
   substdio_fdbuf(&ssmsg,read,fd,ssmsgbuf,sizeof(ssmsgbuf));
   blast(&ssmsg,limit);
   close(fd);
+  m[i].flagseen = 1;
 }
 
 struct commands pop3commands[] = {