diff -ur syslog-ng-2.0.7/src/dnscache.c syslog-ng-2.0.7-patch/src/dnscache.c
--- syslog-ng-2.0.7/src/dnscache.c      2008-01-03 06:59:18.000000000 -0500
+++ syslog-ng-2.0.7-patch/src/dnscache.c        2008-01-27 09:24:52.000000000 -0500
@@ -271,7 +271,7 @@
     }
   g_hash_table_replace(cache, &entry->key, entry);

-  if (g_hash_table_size(cache) > dns_cache_size)
+  if (!persistent && g_hash_table_size(cache) > dns_cache_size)
     {
       /* remove oldest element */
       g_hash_table_remove(cache, &cache_first.next->key);