Index: b/agent/cache.c
===================================================================
--- b/agent/cache.c
+++ b/agent/cache.c
@@ -237,7 +237,7 @@
         case CACHE_MODE_SSH: maxttl = opt.max_cache_ttl_ssh; break;
         default: maxttl = opt.max_cache_ttl; break;
         }
-      if (r->pw && r->created + maxttl < current)
+      if (r->pw && r->ttl >= 0 && r->created + maxttl < current)
         {
           if (DBG_CACHE)
             log_debug ("  expired '%s' (%lus after creation)\n",