Squid-2.2.STABLE4: Unexpected 304 replies
    There was a odd HTTP condition that could cause Squid to return
    "304 Not modified" on plain GET requests without If-Modified-Since.
    This would happen if the first attempt to retreive an object results in a
    5XX error with a Last-Modified header. Squid then automatically tries to
    find another path for fetching the object, but accidently beleived the
    retry was a refresh of the error page...

Index: squid/src/HttpRequest.c
diff -u squid/src/HttpRequest.c:1.1.1.6.22.1 squid/src/HttpRequest.c:1.1.1.6.22.2
--- squid/src/HttpRequest.c:1.1.1.6.22.1	Tue Jul 13 00:37:15 1999
+++ squid/src/HttpRequest.c	Wed Aug  4 22:33:21 1999
@@ -46,6 +46,7 @@
     req->max_forwards = -1;
     req->client_addr = no_addr;
     req->my_addr = no_addr;
+    req->lastmod = -1;
     httpHeaderInit(&req->header, hoRequest);
     return req;
 }
Index: squid/src/client_side.c
diff -u squid/src/client_side.c:1.1.1.42.2.6 squid/src/client_side.c:1.1.1.42.2.7
--- squid/src/client_side.c:1.1.1.42.2.6	Sun Aug  1 17:27:54 1999
+++ squid/src/client_side.c	Wed Aug  4 22:33:21 1999
@@ -310,7 +310,7 @@
     /* delay_id is already set on original store client */
     delaySetStoreClient(entry, http, delayClient(http->request));
 #endif
-    entry->lastmod = http->old_entry->lastmod;
+    http->request->lastmod = http->old_entry->lastmod;
     debug(33, 5) ("clientProcessExpired: lastmod %d\n", (int) entry->lastmod);
     entry->refcount++;		/* EXPIRED CASE */
     http->entry = entry;
Index: squid/src/http.c
diff -u squid/src/http.c:1.1.1.35.2.4 squid/src/http.c:1.1.1.35.2.5
--- squid/src/http.c:1.1.1.35.2.4	Tue Jul 13 01:14:25 1999
+++ squid/src/http.c	Wed Aug  4 22:33:23 1999
@@ -646,8 +646,8 @@
     HttpHeaderPos pos = HttpHeaderInitPos;
     httpHeaderInit(hdr_out, hoRequest);
     /* append our IMS header */
-    if (entry && entry->lastmod > -1 && request->method == METHOD_GET)
-	httpHeaderPutTime(hdr_out, HDR_IF_MODIFIED_SINCE, entry->lastmod);
+    if (request->lastmod > -1 && request->method == METHOD_GET)
+	httpHeaderPutTime(hdr_out, HDR_IF_MODIFIED_SINCE, request->lastmod);
 
     /* decide if we want to do Ranges ourselves 
      * (and fetch the whole object now)
@@ -894,6 +894,7 @@
 	xstrncpy(proxy_req->host, httpState->peer->host, SQUIDHOSTNAMELEN);
 	proxy_req->port = httpState->peer->http_port;
 	proxy_req->flags = orig_req->flags;
+	proxy_req->lastmod = orig_req->lastmod;
 	httpState->request = requestLink(proxy_req);
 	httpState->orig_request = requestLink(orig_req);
 	proxy_req->flags.proxying = 1;
Index: squid/src/store.c
diff -u squid/src/store.c:1.1.1.39.2.4 squid/src/store.c:1.1.1.39.2.5
--- squid/src/store.c:1.1.1.39.2.4	Tue Jul 27 19:34:37 1999
+++ squid/src/store.c	Wed Aug  4 22:33:23 1999
@@ -1249,4 +1249,5 @@
     mem->inmem_hi = mem->inmem_lo = 0;
     httpReplyDestroy(mem->reply);
     mem->reply = httpReplyCreate();
+    e->expires = e->lastmod = e->timestamp = -1;
 }
Index: squid/src/structs.h
diff -u squid/src/structs.h:1.1.1.39.2.12 squid/src/structs.h:1.1.1.39.2.13
--- squid/src/structs.h:1.1.1.39.2.12	Mon Aug  2 22:27:14 1999
+++ squid/src/structs.h	Wed Aug  4 22:33:24 1999
@@ -1326,6 +1326,7 @@
     HierarchyLogEntry hier;
     err_type err_type;
     char *peer_login;		/* Configured peer login:password */
+    time_t lastmod;		/* Used on refreshes */
 };
 
 struct _cachemgr_passwd {