diff -Nur squid-2.6.STABLE2/src/cf.data.pre squid-2.6.STABLE2-zph/src/cf.data.pre
--- squid-2.6.STABLE2/src/cf.data.pre	2006-07-31 04:31:18.000000000 +0300
+++ squid-2.6.STABLE2-zph/src/cf.data.pre	2006-08-13 11:20:01.000000000 +0300
@@ -3119,6 +3119,60 @@
 	to off when using this directive in such configurations.
 DOC_END
 
+NAME: zph_tos_local
+TYPE: int
+DEFAULT: 0
+LOC: Config.zph_tos_local
+DOC_START
+	Allows you to select a TOS/Diffserv value to mark local hits. Read above
+	(tcp_outgoing_tos) for details/requirements about TOS.
+	Default: 0 (disabled).
+DOC_END
+
+NAME: zph_tos_peer
+TYPE: int
+DEFAULT: 0
+LOC: Config.zph_tos_peer
+DOC_START
+	Allows you to select a TOS/Diffserv value to mark peer hits. Read above
+	(tcp_outgoing_tos) for details/requirements about TOS.
+	Default: 0 (disabled).
+DOC_END
+
+NAME: zph_tos_parent
+COMMENT: on|off
+TYPE: onoff
+LOC: Config.onoff.zph_tos_parent
+DEFAULT: on
+DOC_START
+	Set this to off if you want only sibling hits to be marked.
+	If set to on (default), parent hits are being marked too.
+DOC_END
+
+NAME: zph_preserve_miss_tos
+COMMENT: on|off
+TYPE: onoff
+LOC: Config.onoff.zph_preserve_miss_tos
+DEFAULT: on
+DOC_START
+	If set to on (default), any HTTP response towards clients will
+	have the TOS value of the response comming from the remote
+	server masked with the value of zph_preserve_miss_tos_mask.
+	For this to work correctly, you will need to patch your linux
+	kernel with the TOS preserving ZPH patch.
+DOC_END
+
+NAME: zph_preserve_miss_tos_mask
+TYPE: int
+DEFAULT: 255
+LOC: Config.zph_preserve_miss_tos_mask
+DOC_START
+	Allows you to mask certain bits in the TOS received from the
+	remote server, before copying the value to the TOS send towards
+	clients.
+	Default: 255 (TOS from server is not changed).
+DOC_END
+
 NAME: tcp_outgoing_address
 TYPE: acl_address
 DEFAULT: none
diff -Nur squid-2.6.STABLE2/src/client_side.c squid-2.6.STABLE2-zph/src/client_side.c
--- squid-2.6.STABLE2/src/client_side.c	2006-07-24 00:44:22.000000000 +0300
+++ squid-2.6.STABLE2-zph/src/client_side.c	2006-08-13 13:24:01.000000000 +0300
@@ -2660,6 +2660,51 @@
 	return;
     }
     assert(http->out.offset == 0);
+	
+	if ( Config.zph_tos_local || Config.zph_tos_peer ||
+         (Config.onoff.zph_preserve_miss_tos && Config.zph_preserve_miss_tos_mask) )
+    {
+       int need_change = 0;
+       int hit = 0;
+       int tos = 0;
+       int tos_old = 0;
+       int tos_len = sizeof(tos_old);
+       int res;
+                   
+       if (Config.zph_tos_local && isTcpHit(http->log_type)) {     /* local hit */
+           hit = 1;
+           tos = Config.zph_tos_local;
+       } else if (Config.zph_tos_peer &&
+           (http->request->hier.code == SIBLING_HIT ||             /* sibling hit */
+           (Config.onoff.zph_tos_parent &&
+           http->request->hier.code == PARENT_HIT))) {             /* parent hit */
+           hit = 1;
+           tos = Config.zph_tos_peer;
+       }
+       if (http->request->flags.proxy_keepalive) {
+           if (getsockopt(fd, IPPROTO_IP, IP_TOS, &tos_old, &tos_len) < 0) {
+               debug(33, 1) ("ZPH: getsockopt(IP_TOS) on FD %d: %s\n", fd, xstrerror());
+           } else if (hit && tos_old != tos) {     /* HIT: 1-st request, or previous was MISS, */
+               need_change = 1;                    /* or local/parent hit change */
+           } else if (!hit && (tos_old ||  /* MISS: previous was HIT */
+                            Config.onoff.zph_preserve_miss_tos)) { /* TOS copying is on */
+                   if ( Config.onoff.zph_preserve_miss_tos ) {
+                     tos = (entry->mem_obj != NULL) ?
+                           (entry->mem_obj->recvTOS & Config.zph_preserve_miss_tos_mask):0;
+                   } else tos = 0;
+               need_change = 1;
+           } 
+       } else if (hit) {                           /* no keepalive */
+           need_change = 1;
+       }
+       if (need_change) {
+           if (!hit) enter_suid(); /* Setting TOS bit6-7 is privilleged */
+           res = setsockopt(fd, IPPROTO_IP, IP_TOS, &tos, sizeof(tos));
+           if (!hit) leave_suid(); /* Setting bit5-7 is privilleged */
+           if ( res < 0)
+               debug(33, 1) ("ZPH: setsockopt(IP_TOS) on FD %d: %s\n", fd, xstrerror());
+       }
+    }
     rep = http->reply = clientBuildReply(http, buf, size);
     if (!rep) {
 	/* Forward as HTTP/0.9 body with no reply */
diff -Nur squid-2.6.STABLE2/src/http.c squid-2.6.STABLE2-zph/src/http.c
--- squid-2.6.STABLE2/src/http.c	2006-07-26 23:09:33.000000000 +0300
+++ squid-2.6.STABLE2-zph/src/http.c	2006-08-13 13:25:54.000000000 +0300
@@ -1262,7 +1262,51 @@
     peer *p = httpState->peer;
     CWCB *sendHeaderDone;
     int fd = httpState->fd;
-
+    int tos, tos_len;
+    
+	/* ZPH patch starts here (M.Stavrev 25-05-2005)
+	 * Retrieve connection peer's TOS value (which its SYN_ACK TCP segment
+	 * was encapsulated into an IP packet)
+	 */
+    if ( entry && entry->mem_obj ) { // Is this check necessary ? Seems not, but
+				 // have no time to investigate further.
+	    entry->mem_obj->recvTOS = 0;
+	    tos = 1;
+	    tos_len = sizeof(tos);
+	 	if ( setsockopt(fd,SOL_IP, IP_RECVTOS, &tos, tos_len) == 0 ) {
+		    unsigned char buf[128];
+		    int len = 128;
+		    if (getsockopt(fd, SOL_IP, IP_PKTOPTIONS, buf, &len) == 0)
+		    {
+		    	/* Parse the PKTOPTIONS structure to locate the TOS data message
+		    	 * prepared in the kernel by the ZPH incoming TCP TOS preserving
+		    	 * patch. In 99,99% the TOS should be located at buf[12], but
+		    	 * let's do it the right way.
+		    	 */
+		    	unsigned char * p = buf;
+		    	while ( p-buf < len ) {
+		    		struct cmsghdr * o = (struct cmsghdr*)p;
+		    		if ( o->cmsg_len <= 0 || o->cmsg_len > 52 )
+		    		   break;
+		    		if ( o->cmsg_level == SOL_IP && o->cmsg_type == IP_TOS ) {
+	    			   entry->mem_obj->recvTOS = (unsigned char)(*(int*)
+			    	   						(p + sizeof(struct cmsghdr)));
+				       debug(11, 5) ("ZPH: Incomming TOS=%d on FD %d\n",
+				       			entry->mem_obj->recvTOS, fd );
+			    	   break;
+		    		}
+		    		p += o->cmsg_len;
+		    	}
+		    } else {
+		    	debug(11, 5) ("ZPH: getsockopt(IP_PKTOPTIONS) on FD %d: %s\n",
+		    				 fd, xstrerror());
+		    }
+		} else {
+	    	debug(11, 5) ("ZPH: setsockopt(IP_RECVTOS) on FD %d: %s\n",
+	    					 fd, xstrerror());
+		}
+    }
+	/* ZPH patch ends here */    
     debug(11, 5) ("httpSendRequest: FD %d: httpState %p.\n", fd, httpState);
 
     /* Schedule read reply. (but no timeout set until request fully sent) */
diff -Nur squid-2.6.STABLE2/src/structs.h squid-2.6.STABLE2-zph/src/structs.h
--- squid-2.6.STABLE2/src/structs.h	2006-07-31 02:27:03.000000000 +0300
+++ squid-2.6.STABLE2-zph/src/structs.h	2006-08-13 12:57:57.000000000 +0300
@@ -667,6 +667,8 @@
 	int relaxed_header_parser;
 	int accel_no_pmtu_disc;
 	int global_internal_static;
+	int zph_tos_parent;
+	int zph_preserve_miss_tos;	
 	int httpd_suppress_version_string;
 	int via;
 	int check_hostnames;
@@ -791,6 +793,9 @@
     int sleep_after_fork;	/* microseconds */
     time_t minimum_expiry_time;	/* seconds */
     external_acl *externalAclHelperList;
+	int zph_tos_local;
+   	int zph_tos_peer;
+	int zph_preserve_miss_tos_mask;    
     errormap *errorMapList;
 #if USE_SSL
     struct {
@@ -1693,6 +1698,7 @@
     const char *vary_encoding;
     StoreEntry *ims_entry;
     time_t refresh_timestamp;
+	unsigned char recvTOS; /* ZPH patch - stores remote server's TOS */
 };
 
 struct _StoreEntry {