diff -Naur APC-3.1.13/apc_bin.c APC-3.1.13-fix-warnings/apc_bin.c
--- APC-3.1.13/apc_bin.c	2012-09-03 18:52:51.000000000 +0200
+++ APC-3.1.13-fix-warnings/apc_bin.c	2013-01-09 12:40:30.906380305 +0100
@@ -719,7 +719,7 @@
     apc_bd_alloc_ex(pool_ptr, sizeof(apc_pool) TSRMLS_CC);
     ctxt.pool = apc_pool_create(APC_UNPOOL, apc_bd_alloc, apc_bd_free, NULL, NULL TSRMLS_CC);  /* ideally the pool wouldn't be alloc'd as part of this */
     if (!ctxt.pool) { /* TODO need to cleanup */
-        apc_warning("Unable to allocate memory for pool." TSRMLS_CC);
+        php_log_err("Unable to allocate memory for pool." TSRMLS_CC);
         return NULL;
     }
     ctxt.copy = APC_COPY_IN_OPCODE; /* avoid stupid ALLOC_ZVAL calls here, hack */
@@ -894,7 +894,7 @@
     for(i = 0; i < bd->num_entries; i++) {
         ctxt.pool = apc_pool_create(APC_SMALL_POOL, apc_sma_malloc, apc_sma_free, apc_sma_protect, apc_sma_unprotect TSRMLS_CC);
         if (!ctxt.pool) { /* TODO need to cleanup previous pools */
-            apc_warning("Unable to allocate memory for pool." TSRMLS_CC);
+            php_log_err("Unable to allocate memory for pool." TSRMLS_CC);
             goto failure;
         }
         ep = &bd->entries[i];
diff -Naur APC-3.1.13/apc_cache.c APC-3.1.13-fix-warnings/apc_cache.c
--- APC-3.1.13/apc_cache.c	2012-09-03 18:52:51.000000000 +0200
+++ APC-3.1.13-fix-warnings/apc_cache.c	2013-01-09 12:42:24.598958952 +0100
@@ -1334,6 +1334,7 @@
 /* {{{ apc_cache_is_last_key */
 zend_bool apc_cache_is_last_key(apc_cache_t* cache, apc_cache_key_t* key, time_t t TSRMLS_DC)
 {
+    char *log_message;
     apc_keyid_t *lastkey = &cache->header->lastkey;
     unsigned int keylen = key->data.user.identifier_len;
 #ifdef ZTS
@@ -1350,7 +1351,10 @@
         if(lastkey->mtime == t && FROM_DIFFERENT_THREAD(lastkey)) {
             /* potential cache slam */
             if(APCG(slam_defense)) {
-                apc_debug("Potential cache slam averted for key '%s'" TSRMLS_CC, key->data.user.identifier);
+                log_message = emalloc((key->data.user.identifier_len + 40) * sizeof(char));
+                sprintf(log_message, "Potential cache slam averted for key '%s'", key->data.user.identifier);
+                php_log_err(log_message TSRMLS_CC);
+                efree(log_message);
                 return 1;
             }
         }
diff -Naur APC-3.1.13/apc_main.c APC-3.1.13-fix-warnings/apc_main.c
--- APC-3.1.13/apc_main.c	2012-09-03 18:52:51.000000000 +0200
+++ APC-3.1.13-fix-warnings/apc_main.c	2013-01-09 12:40:30.909380268 +0100
@@ -403,7 +403,7 @@
     ctxt.pool = apc_pool_create(APC_MEDIUM_POOL, apc_sma_malloc, apc_sma_free, 
                                                  apc_sma_protect, apc_sma_unprotect TSRMLS_CC);
     if (!ctxt.pool) {
-        apc_warning("Unable to allocate memory for pool." TSRMLS_CC);
+        php_log_err("Unable to allocate memory for pool." TSRMLS_CC);
         return FAILURE;
     }
     ctxt.copy = APC_COPY_IN_OPCODE;
@@ -528,7 +528,7 @@
         ctxt.pool = apc_pool_create(APC_UNPOOL, apc_php_malloc, apc_php_free,
                                                 apc_sma_protect, apc_sma_unprotect TSRMLS_CC);
         if (!ctxt.pool) {
-            apc_warning("Unable to allocate memory for pool." TSRMLS_CC);
+            php_log_err("Unable to allocate memory for pool." TSRMLS_CC);
             return old_compile_file(h, type TSRMLS_CC);
         }
         ctxt.copy = APC_COPY_OUT_OPCODE;
diff -Naur APC-3.1.13/php_apc.c APC-3.1.13-fix-warnings/php_apc.c
--- APC-3.1.13/php_apc.c	2012-09-03 18:52:51.000000000 +0200
+++ APC-3.1.13-fix-warnings/php_apc.c	2013-01-09 12:41:06.435936125 +0100
@@ -589,7 +589,7 @@
     ctxt.pool = apc_pool_create(APC_SMALL_POOL, apc_sma_malloc, apc_sma_free, apc_sma_protect, apc_sma_unprotect TSRMLS_CC);
     if (!ctxt.pool) {
         HANDLE_UNBLOCK_INTERRUPTIONS();
-        apc_warning("Unable to allocate memory for pool." TSRMLS_CC);
+        php_log_err("Unable to allocate memory for pool." TSRMLS_CC);
         return 0;
     }
     ctxt.copy = APC_COPY_IN_USER;
@@ -838,7 +838,7 @@
 
     ctxt.pool = apc_pool_create(APC_UNPOOL, apc_php_malloc, apc_php_free, NULL, NULL TSRMLS_CC);
     if (!ctxt.pool) {
-        apc_warning("Unable to allocate memory for pool." TSRMLS_CC);
+        php_log_err("Unable to allocate memory for pool." TSRMLS_CC);
         RETURN_FALSE;
     }
     ctxt.copy = APC_COPY_OUT_USER;