diff --git a/CHANGES b/CHANGES
index 53ab357..84a1c59 100644
--- a/CHANGES
+++ b/CHANGES
@@ -1,6 +1,10 @@
                                                          -*- coding: utf-8 -*-
 Changes with Apache 2.5.0
 
+  *) core: In maintainer mode, replace apr_palloc with a version that
+     initializes the allocated memory with non-zero values, except if
+     AP_DEBUG_NO_ALLOC_POISON is defined.
+
   *) mod_log_config: Check during config test that directories for access logs
      exist. PR 29941. [Stefan Fritsch]
 
diff --git a/include/ap_mmn.h b/include/ap_mmn.h
index e77690d..7290324 100644
--- a/include/ap_mmn.h
+++ b/include/ap_mmn.h
@@ -393,6 +393,7 @@
  * 20120204.0 (2.5.0-dev)  Remove ap_create_core_ctx(), ap_core_ctx_get_bb();
  *                         add insert_network_bucket hook, AP_DECLINED
  * 20120211.0 (2.5.0-dev)  Change re_nsub in ap_regex_t from apr_size_t to int.
+ * 20120211.0 (2.5.0-dev)  Add ap_palloc_debug, ap_pcalloc_debug
  */
 
 #define MODULE_MAGIC_COOKIE 0x41503235UL /* "AP25" */
@@ -400,7 +401,7 @@
 #ifndef MODULE_MAGIC_NUMBER_MAJOR
 #define MODULE_MAGIC_NUMBER_MAJOR 20120211
 #endif
-#define MODULE_MAGIC_NUMBER_MINOR 0                   /* 0...n */
+#define MODULE_MAGIC_NUMBER_MINOR 1                   /* 0...n */
 
 /**
  * Determine if the server's current MODULE_MAGIC_NUMBER is at least a
diff --git a/include/httpd.h b/include/httpd.h
index 6ffdef2..82a3fff 100644
--- a/include/httpd.h
+++ b/include/httpd.h
@@ -2068,6 +2068,8 @@
 AP_DECLARE(const char *) ap_strrchr_c(const char *s, int c);
 AP_DECLARE(char *) ap_strstr(char *s, const char *c);
 AP_DECLARE(const char *) ap_strstr_c(const char *s, const char *c);
+AP_DECLARE(void *) ap_palloc_debug(apr_pool_t *p, apr_size_t size);
+AP_DECLARE(void *) ap_pcalloc_debug(apr_pool_t *p, apr_size_t size);
 
 #ifdef AP_DEBUG
 
@@ -2078,6 +2080,21 @@
 #undef strstr
 # define strstr(s, c)  ap_strstr(s,c)
 
+#ifndef AP_DEBUG_NO_ALLOC_POISON
+/*
+ * ap_palloc_debug initializes allocated memory to non-zero
+ */
+#define apr_palloc     ap_palloc_debug
+/*
+ * this is necessary to avoid useless double memset of memory
+ * with ap_palloc_debug
+ */
+#ifdef apr_pcalloc
+#undef apr_pcalloc
+#endif
+#define apr_pcalloc    ap_pcalloc_debug
+#endif
+
 #else
 
 /** use this instead of strchr */
diff --git a/server/util_debug.c b/server/util_debug.c
index 41250da..52f9415 100644
--- a/server/util_debug.c
+++ b/server/util_debug.c
@@ -223,3 +223,20 @@
 {
     ((void **)cv)[AP_CORE_MODULE_INDEX] = val;
 }
+
+#if defined(apr_palloc)
+#undef apr_palloc
+#endif
+AP_DECLARE(void *) ap_palloc_debug(apr_pool_t *p, apr_size_t size)
+{
+    /* poison uninitialized memory */
+    return memset(apr_palloc(p, size), 0xEE, size);
+}
+
+#if defined(apr_pcalloc)
+#undef apr_pcalloc
+#endif
+AP_DECLARE(void *) ap_pcalloc_debug(apr_pool_t *p, apr_size_t size)
+{
+    return memset(apr_palloc(p, size), 0, size);
+}