Надо же, до сих пор прикладывается (с -F 60).

Для удобства -- ссылка на письмо:
http://www.lexa.ru/apache-talk/msg06354.html
оригинальный патч:
http://fly.osdn.org.ua/~mike/works/apache/apache-1.3.23-unlo...
rediff для 1.3.41 (похоже, включу в сборку для ALT Linux):
http://fly.osdn.org.ua/~mike/works/apache/apache-1.3.41-unlo...
и на всякий вклеиваю его:

diff -Naur apache_1.3.41-orig/src/modules/standard/mod_rewrite.c apache_1.3.41/src/modules/standard/mod_rewrite.c
--- apache_1.3.41-orig/src/modules/standard/mod_rewrite.c    2006-07-27 20:09:03 +0300
+++ apache_1.3.41/src/modules/standard/mod_rewrite.c    2008-03-31 19:33:24 +0300
@@ -62,6 +62,17 @@
static LONG locking_sem = 0;
#endif

+#ifndef REWRITE_MAX_RULES
+#define REWRITE_MAX_RULES 300
+#endif
+#ifndef REWRITE_MAX_REDIRECTS
+#define REWRITE_MAX_REDIRECTS 50
+#endif
+
+#define REWRITE_FIXUP_NOTE "rewrite_fixup_redirect"
+
+int redirect_count;        /* Счетчик циклов для fixup */
+
/*
** +-------------------------------------------------------+
** |                                                       |
@@ -1345,6 +1356,34 @@
         return FORBIDDEN;
     }

+    /* Проверим и установим флаг первого запроса */
+    {
+        request_rec *q;
+        int note_found = 0;
+        for (q = r; q != NULL; q = q->prev) {
+            if( ap_table_get(q->notes, REWRITE_FIXUP_NOTE) != NULL ) {
+                note_found = 1;
+                break;
+            }
+        }
+        ap_table_set(r->notes, REWRITE_FIXUP_NOTE, "OK");
+        
+        if( !note_found ) {
+            redirect_count = REWRITE_MAX_REDIRECTS;
+            rewritelog(r, 3, "setting redirect count notice" );
+        }
+    }
+
+    /* Проверим количество циклов */
+    if( redirect_count-- <= 0 ) {
+        /* очень много итераций */
+        ap_log_rerror(APLOG_MARK, APLOG_ERR, r,
+            "too many rewrite internal redirects: %s", r->uri);
+        return HTTP_INTERNAL_SERVER_ERROR;
+    }
+
+    rewritelog(r, 3, "internal redirect count: %d", redirect_count );
+    
     /*
      *  remember the current filename before rewriting for later check
      *  to prevent deadlooping because of internal redirects
@@ -1359,6 +1398,13 @@
     if (rulestatus) {
         unsigned skip;

+        if (strlen(r->filename) > 20 &&
+            strncmp(r->filename, "too_many_iterations:", 20) == 0) {
+            /* очень много итераций */
+            ap_log_rerror(APLOG_MARK, APLOG_ERR, r,
+                "too many rewrite rules (possible loop): %s", r->uri);
+            return HTTP_INTERNAL_SERVER_ERROR;
+        } else
         if (strlen(r->filename) > 6 &&
             strncmp(r->filename, "proxy:", 6) == 0) {
             /* it should go on as an internal proxy request */
@@ -1671,6 +1717,7 @@
     int changed;
     int rc;
     int s;
+    int loopcount = REWRITE_MAX_RULES;

     /*
      *  Iterate over all existing rules
@@ -1679,6 +1726,13 @@
     changed = 0;
     loop:
     for (i = 0; i < rewriterules->nelts; i++) {
+        if( loopcount-- <= 0 ) {
+            rewritelog(r, 2, "too many iterations '%s'", r->filename);
+            r->filename = ap_pstrcat(r->pool, "too_many_iterations:", r->filename, NULL);
+            changed = ACTION_NORMAL;
+            break;
+        }
+        
         p = &entries[i];

         /*