diff --git a/server/async.c b/server/async.c
index baed133..879616d 100644
--- a/server/async.c
+++ b/server/async.c
@@ -263,6 +263,7 @@
         if (async->data.apc)
         {
             apc_call_t data;
+            memset( &data, 0, sizeof(data) );
             data.type         = APC_USER;
             data.user.func    = async->data.apc;
             data.user.args[0] = (unsigned long)async->data.arg;