diff -urN squid-2.5.STABLE12/src/icap_respmod.c squid-2.5.STABLE12-http0.9fix/src/icap_respmod.c
--- squid-2.5.STABLE12/src/icap_respmod.c	2006-01-05 16:26:37.000000000 +0000
+++ squid-2.5.STABLE12-http0.9fix/src/icap_respmod.c	2006-01-05 16:51:08.000000000 +0000
@@ -104,6 +104,9 @@
 	consumed = -1;
 	o2 = -1;
 	memBufDefInit(&mb_hdr);
+	httpBuildRequestPrefix(icap->request, icap->request,
+			       icap->respmod.entry, &mb_hdr, icap->http_flags);
+	o3 = mb_hdr.size;
     } else {
 
 	hlen = headersEnd(icap->respmod.req_hdr_copy.buf,
@@ -132,12 +135,12 @@
 	httpBuildRequestPrefix(icap->request, icap->request,
 	    icap->respmod.entry, &mb_hdr, icap->http_flags);
 	o2 = mb_hdr.size;
-    }
 
-    /* Copy response header - Append to request header mbuffer */
-    memBufAppend(&mb_hdr,
-	icap->respmod.req_hdr_copy.buf, icap->respmod.req_hdr_copy.size);
-    o3 = mb_hdr.size;
+    	/* Copy response header - Append to request header mbuffer */
+	memBufAppend(&mb_hdr,
+		     icap->respmod.req_hdr_copy.buf, icap->respmod.req_hdr_copy.size);
+	o3 = mb_hdr.size;
+    }
 
     service = icap->current_service;
     assert(service);