commit 07e79a0822fcb986f5734a11f878fd6b3517e910
Author: devhc <devhc@.(none)>
Date:   Fri May 13 23:35:57 2011 +0200

    ensure that ent->classname is always non-null (for entity numbers up to level.num_entities-1, and ENTITYNUM_WORLD, and ENTITYNUM_NONE), for player entities and #ENTITYNUM_NONE in particular

diff --git a/src/game/g_main.c b/src/game/g_main.c
index 507a5d6..5d42930 100644
--- a/src/game/g_main.c
+++ b/src/game/g_main.c
@@ -622,6 +622,9 @@ void G_InitGame( int levelTime, int randomSeed, int restart )
   // range are NEVER anything but clients
   level.num_entities = MAX_CLIENTS;
 
+  for( i = 0; i < MAX_CLIENTS; i++ )
+    g_entities[ i ].classname = "clientslot";
+
   // let the server system know where the entites are
   trap_LocateGameData( level.gentities, level.num_entities, sizeof( gentity_t ),
     &level.clients[ 0 ].ps, sizeof( level.clients[ 0 ] ) );
diff --git a/src/game/g_spawn.c b/src/game/g_spawn.c
index bdb5ff7..b249a10 100644
--- a/src/game/g_spawn.c
+++ b/src/game/g_spawn.c
@@ -600,8 +600,13 @@ void SP_worldspawn( void )
     trap_Cvar_Set( "g_disabledBuildables", s );
 
   g_entities[ ENTITYNUM_WORLD ].s.number = ENTITYNUM_WORLD;
+  g_entities[ ENTITYNUM_WORLD ].r.ownerNum = ENTITYNUM_NONE;
   g_entities[ ENTITYNUM_WORLD ].classname = "worldspawn";
 
+  g_entities[ ENTITYNUM_NONE ].s.number = ENTITYNUM_NONE;
+  g_entities[ ENTITYNUM_NONE ].r.ownerNum = ENTITYNUM_NONE;
+  g_entities[ ENTITYNUM_NONE ].classname = "nothing";
+
   if( g_restarted.integer )
     trap_Cvar_Set( "g_restarted", "0" );