Provide escaping for the ampersand in mod_rewrite
diff -ur httpd-2.2.0/modules/mappers/mod_rewrite.c httpd-2.2.0.patched/modules/mappers/mod_rewrite.c
--- httpd-2.2.0/modules/mappers/mod_rewrite.c	2005-11-10 07:20:05.000000000 -0800
+++ httpd-2.2.0.patched/modules/mappers/mod_rewrite.c	2006-02-04 13:52:34.000000000 -0800
@@ -1075,6 +1075,30 @@
     return ap_escape_uri(r->pool, key);
 }
 
+static char *rewrite_mapfunc_ampescape(request_rec *r, char *key) {
+	/* we only need to escape the ampersand */
+
+	unsigned char *copy = (char *)apr_palloc(r->pool, 3 * strlen(key) + 3);
+	const unsigned char *s = (const unsigned char *)key;
+	unsigned char *d = (unsigned char *)copy;
+	unsigned c;
+
+	while ((c = *s)) {
+		if (c == '&') {
+			*d++ = '%';
+			*d++ = '2';
+			*d++ = '6';
+		} else {
+			*d++ = c;
+		}
+		++s;
+	}
+	*d = '\0';
+
+	return copy;
+}
+
+
 static char *rewrite_mapfunc_unescape(request_rec *r, char *key)
 {
     ap_unescape_url(key);
@@ -4011,6 +4035,7 @@
         map_pfn_register("tolower", rewrite_mapfunc_tolower);
         map_pfn_register("toupper", rewrite_mapfunc_toupper);
         map_pfn_register("escape", rewrite_mapfunc_escape);
+		map_pfn_register("ampescape", rewrite_mapfunc_ampescape);
         map_pfn_register("unescape", rewrite_mapfunc_unescape);
     }
     return OK;