Index: src/backend/ipcsharedmemory/ipcsharedmemoryprovider.php
--- src/backend/ipcsharedmemory/ipcsharedmemoryprovider.php.orig
+++ src/backend/ipcsharedmemory/ipcsharedmemoryprovider.php
@@ -42,7 +42,7 @@ class IpcSharedMemoryProvider implements IIpcProvider 
         $this->allocate = $allocate;
 
         if ($this->initSharedMem())
-            ZLog::Write(LOGLEVEL_DEBUG, sprintf("%s(): Initialized mutexid %s and memid %s.", $class, $this->mutexid, $this->memid));
+            ZLog::Write(LOGLEVEL_DEBUG, sprintf("%s(): Initialized mutexid %s and memid %s.", $class, $this->mutexid::class, $this->memid::class));
     }
 
     /**
