--- polipo-1.0.4.1.old/http_parse.c
+++ polipo-1.0.4.1/http_parse.c
@@ -39,7 +39,7 @@
     atomVia, atomVary, atomExpect, atomAuthorization,
     atomSetCookie, atomCookie, atomCookie2,
     atomXPolipoDate, atomXPolipoAccess, atomXPolipoLocation, 
-    atomXPolipoBodyOffset;
+    atomXPolipoBodyOffset, atomUserAgent;
 
 AtomPtr atomContentType, atomContentEncoding;
 
@@ -109,6 +109,7 @@
     A(atomXPolipoAccess, "x-polipo-access");
     A(atomXPolipoLocation, "x-polipo-location");
     A(atomXPolipoBodyOffset, "x-polipo-body-offset");
+    A(atomUserAgent, "user-agent");
 #undef A
     return;
 
@@ -520,6 +521,8 @@
     int i;
     int name_start, name_end, value_start, value_end;
 
+    *value_start_return = 0;
+
     if(buf[start] == '\n') {
         *name_start_return = -1;
         return start + 1;
@@ -767,6 +770,7 @@
     AtomListPtr hopToHop = NULL;
     HTTPRangeRec range = {-1, -1, -1}, content_range = {-1, -1, -1};
     int haveCacheControl = 0;
+    int KeepOrigUserAgent = 0;
  
 #define RESIZE_HBUF() \
     do { \
@@ -799,7 +803,89 @@
 
         name = internAtomLowerN(buf + name_start, name_end - name_start);
 
-        if(name == atomConnection) {
+//--------------------------------------------------------------------
+
+// The following code is an attempt to bypass a web-server problem.
+
+// Details:  If you try to use a  Mozilla-based browser  (such as Ice-
+// Cat) with "polipo",  some web sites will  reject connections unless
+// you  change  the reported user agent from  "Mozilla/5.0 ..." (etc.)
+// to a non-Mozilla value. They don't like to see a non-Mozilla client
+// [polipo] connecting with a  Mozilla user-agent string.  It's viewed
+// as a sign that the client may be "bad"  (for example, a spammer ad-
+// dress harvester).
+
+// To complicate matters,  other web sites  allow "polipo"  to connect
+// with a Mozilla user-agent string,  and (in fact) the sites may mal-
+// function if a Mozilla user-agent string (or a user-agent string for
+// another major browser) *isn't* used. "yahoo.com" is one example.
+
+// This code checks the  "host:" and "user-agent:" fields specified by
+// each HTTP request.  If the  "user-agent" field is  present, and  it
+// starts with "Mozilla", and the "host" field isn't  present, or it's
+// not one of  the hosts that  *requires* the "Mozilla" setting,  this
+// code replaces the string "Mozilla" with "XPolipo".  This solves the
+// problem for some sites. However, additional changes may be required
+// for other sites.
+
+// Note:  The replacement string used must be  exactly the same length
+// as the original string (i.e., seven characters).
+
+// This  isn't a  perfect solution:  a. There may be  side-effects. b.
+// Some web sites may reject  connections from  Mozilla-based browsers
+// operating through "polipo"  whether or not the user-agent string is
+// changed.
+
+        if (name == atomHost)
+        {
+            char *xp = &buf [value_start];
+
+            if (value_start > 0)
+            {
+                char *bp;
+
+#ifdef NOTDEF
+                if (!strncmp (xp, "google.com"        , 10) ||
+                    !strncmp (xp, "yahoo.com"         ,  9) ||
+                    !strncmp (xp, "groups.google.com" , 17) ||
+                    !strncmp (xp, "mail.yahoo.com"    , 14) ||
+                    !strncmp (xp, "www.google.com"    , 14) ||
+                    !strncmp (xp, "www.yahoo.com"     , 13))
+                {
+                    KeepOrigUserAgent = 1;
+                }
+#else
+                for (bp = xp; *bp != '\0'; bp++)
+                {               // Not perfect, but good enough
+                    if ((*bp == 'g') && (bp [1] == 'o') &&
+                        !strncmp (bp, "google.com", 10))
+                    {
+                        KeepOrigUserAgent = 1;
+                    }
+
+                    if ((*bp == 'y') && (bp [1] == 'a') &&
+                        !strncmp (bp, "yahoo.com", 9))
+                    {
+                        KeepOrigUserAgent = 1;
+                    }
+                }
+#endif
+            }
+        }
+
+        if ((name == atomUserAgent) &&
+            (value_start > 0) && !KeepOrigUserAgent)
+        {
+            char *xp = &buf [value_start];
+
+            if (!strncmp (xp, "Mozilla", 7))
+            {
+                strncpy  (xp, "XPolipo", 7);
+            }
+        }
+
+        if (name == atomConnection)
+        {
             j = getNextTokenInList(buf, value_start, 
                                    &token_start, &token_end, NULL, NULL,
                                    &end);