diff -up centerim-4.22.10/libicq2000/libicq2000/sigslot.h.orig centerim-4.22.10/libicq2000/libicq2000/sigslot.h
--- centerim-4.22.10/libicq2000/libicq2000/sigslot.h.orig	2011-07-01 18:30:14.000000000 +0200
+++ centerim-4.22.10/libicq2000/libicq2000/sigslot.h	2011-07-01 18:33:37.000000000 +0200
@@ -82,6 +82,7 @@
 #ifndef SIGSLOT_H__
 #define SIGSLOT_H__
 
+#include <cstddef>
 #include <set>
 #include <list>