--- a/src/group_cmd.cpp	Wed Jul 23 18:23:12 2008 +0000
+++ b/src/group_cmd.cpp	Wed Jul 23 18:41:15 2008 +0000
@@ -51,7 +51,8 @@
 Group::Group(PlayerID owner)
 {
 	this->owner = owner;
-	this->num_engines = CallocT<uint16>(GetEnginePoolSize());
+
+	if (this->IsValid()) this->num_engines = CallocT<uint16>(GetEnginePoolSize());
 }
 
 Group::~Group()