Index: http_filters.c
===================================================================
--- http_filters.c	(revision 6036)
+++ http_filters.c	(working copy)
@@ -186,19 +186,23 @@
         if ((ctx->state == BODY_CHUNK ||
             (ctx->state == BODY_LENGTH && ctx->remaining > 0)) &&
             f->r->expecting_100 && f->r->proto_num >= HTTP_VERSION(1,1)) {
-            char *tmp;
-            apr_bucket_brigade *bb;
+            if (ap_is_HTTP_CLIENT_ERROR(f->r->status)) {
+                ctx->remaining = 0;
+            } else {
+                char *tmp;
+                apr_bucket_brigade *bb;
 
-            tmp = apr_pstrcat(f->r->pool, AP_SERVER_PROTOCOL, " ",
-                              ap_get_status_line(100), CRLF CRLF, NULL);
-            bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
-            e = apr_bucket_pool_create(tmp, strlen(tmp), f->r->pool,
-                                       f->c->bucket_alloc);
-            APR_BRIGADE_INSERT_HEAD(bb, e);
-            e = apr_bucket_flush_create(f->c->bucket_alloc);
-            APR_BRIGADE_INSERT_TAIL(bb, e);
+                tmp = apr_pstrcat(f->r->pool, AP_SERVER_PROTOCOL, " ",
+                                  ap_get_status_line(100), CRLF CRLF, NULL);
+                bb = apr_brigade_create(f->r->pool, f->c->bucket_alloc);
+                e = apr_bucket_pool_create(tmp, strlen(tmp), f->r->pool,
+                                           f->c->bucket_alloc);
+                APR_BRIGADE_INSERT_HEAD(bb, e);
+                e = apr_bucket_flush_create(f->c->bucket_alloc);
+                APR_BRIGADE_INSERT_TAIL(bb, e);
 
-            ap_pass_brigade(f->c->output_filters, bb);
+                ap_pass_brigade(f->c->output_filters, bb);
+            }
         }
 
         /* We can't read the chunk until after sending 100 if required. */