diff --git a/core/database.class.php b/core/database.class.php
index 1e8da970..97f7c717 100644
--- a/core/database.class.php
+++ b/core/database.class.php
@@ -199,6 +199,9 @@ class MemcacheCache implements CacheEngine {
 
 	public function get($key) {
 		assert(!is_null($key));
+		if((DEBUG_CACHE === true) || (is_null(DEBUG_CACHE) && @$_GET['DEBUG_CACHE'])) {
+			file_put_contents("data/cache.log", "Cache lookup: $key\n", FILE_APPEND);
+		}
 		$val = $this->memcache->get($key);
 		if($val !== false) {
 			$this->hits++;
diff --git a/core/sys_config.inc.php b/core/sys_config.inc.php
index 6473ebc5..4190358f 100644
--- a/core/sys_config.inc.php
+++ b/core/sys_config.inc.php
@@ -24,6 +24,7 @@ _d("DATABASE_KA", true);     // string   Keep database connection alive
 _d("CACHE_DSN", null);       // string   cache connection details
 _d("DEBUG", false);          // boolean  print various debugging details
 _d("DEBUG_SQL", false);      // boolean  dump SQL queries to data/sql.log
+_d("DEBUG_CACHE", false);    // boolean  dump cache queries to data/cache.log
 _d("COVERAGE", false);       // boolean  activate xdebug coverage monitor
 _d("CONTEXT", null);         // string   file to log performance data into
 _d("CACHE_HTTP", false);     // boolean  output explicit HTTP caching headers