diff --git a/src/actor.h b/src/actor.h
index 13425e48a..53145b7c1 100644
--- a/src/actor.h
+++ b/src/actor.h
@@ -39,6 +39,7 @@
 #include "textures/textures.h"
 #include "r_blend.h"
 #include "s_sound.h"
+#include "memarena.h"
 
 struct subsector_t;
 //
@@ -760,6 +761,7 @@ public:
 	fixed_t GetGravity() const;
 	bool IsSentient() const;
 	const char *GetTag(const char *def = NULL) const;
+	void SetTag(const char *def);
 
 
 // info for drawing
@@ -855,7 +857,7 @@ public:
 	int				activationtype;	// How the thing behaves when activated with USESPECIAL or BUMPSPECIAL
 	int				lastbump;		// Last time the actor was bumped, used to control BUMPSPECIAL
 	int				Score;			// manipulated by score items, ACS or DECORATE. The engine doesn't use this itself for anything.
-	FNameNoInit		Tag;			// Strife's tag name. FIXME: should be case sensitive!
+	FString *		Tag;			// Strife's tag name.
 
 	AActor			*BlockingMobj;	// Actor that blocked the last move
 	line_t			*BlockingLine;	// Line that blocked the last move
@@ -927,6 +929,7 @@ public:
 private:
 	static AActor *TIDHash[128];
 	static inline int TIDHASH (int key) { return key & 127; }
+	static FSharedStringArena mStringPropertyData;
 
 	friend class FActorIterator;
 
diff --git a/src/memarena.cpp b/src/memarena.cpp
index c44586dee..21cee59a6 100644
--- a/src/memarena.cpp
+++ b/src/memarena.cpp
@@ -373,4 +373,5 @@ void FSharedStringArena::FreeAll()
 		FreeBlocks = block;
 	}
 	memset(Buckets, 0, sizeof(Buckets));
+	TopBlock = NULL;
 }
diff --git a/src/memarena.h b/src/memarena.h
index e933fc072..823672018 100644
--- a/src/memarena.h
+++ b/src/memarena.h
@@ -31,6 +31,9 @@
 **
 */
 
+#ifndef __MEMARENA_H
+#define __MEMARENA_H
+
 #include "zstring.h"
 
 // A general purpose arena.
@@ -81,3 +84,6 @@ protected:
 private:
 	void *Alloc(size_t size) { return NULL; }	// No access to FMemArena::Alloc for outsiders.
 };
+
+
+#endif
\ No newline at end of file
diff --git a/src/p_acs.cpp b/src/p_acs.cpp
index 63c3f0a6c..8b54ffce2 100644
--- a/src/p_acs.cpp
+++ b/src/p_acs.cpp
@@ -2709,7 +2709,7 @@ void DLevelScript::DoSetActorProperty (AActor *actor, int property, int value)
 		actor->Score = value;
 
 	case APROP_NameTag:
-		actor->Tag = FBehavior::StaticLookupString(value);
+		actor->SetTag(FBehavior::StaticLookupString(value));
 		break;
 
 	case APROP_DamageFactor:
diff --git a/src/p_mobj.cpp b/src/p_mobj.cpp
index 39a17bf76..31302cbc8 100644
--- a/src/p_mobj.cpp
+++ b/src/p_mobj.cpp
@@ -300,7 +300,6 @@ void AActor::Serialize (FArchive &arc)
 		<< pushfactor
 		<< Species
 		<< Score
-		<< Tag
 		<< lastpush << lastbump
 		<< PainThreshold
 		<< DamageFactor
@@ -309,6 +308,17 @@ void AActor::Serialize (FArchive &arc)
 		<< PoisonDamage << PoisonDuration << PoisonPeriod
 		<< ConversationRoot << Conversation;
 
+	{
+		FString tagstr;
+		if (arc.IsStoring() && Tag != NULL && Tag->Len() > 0) tagstr = *Tag;
+		arc << tagstr;
+		if (arc.IsLoading())
+		{
+			if (tagstr.Len() == 0) Tag = NULL;
+			else Tag = mStringPropertyData.Alloc(tagstr);
+		}
+	}
+
 	if (arc.IsLoading ())
 	{
 		touching_sectorlist = NULL;
@@ -5521,11 +5531,13 @@ bool AActor::IsSentient() const
 }
 
 
+FSharedStringArena AActor::mStringPropertyData;
+
 const char *AActor::GetTag(const char *def) const
 {
-	if (Tag != NAME_None)
+	if (Tag != NULL)
 	{
-		const char *tag = Tag.GetChars();
+		const char *tag = Tag->GetChars();
 		if (tag[0] == '$')
 		{
 			return GStrings(tag + 1);
@@ -5545,6 +5557,18 @@ const char *AActor::GetTag(const char *def) const
 	}
 }
 
+void AActor::SetTag(const char *def)
+{
+	if (def == NULL || *def == 0) 
+	{
+		Tag = NULL;
+	}
+	else 
+	{
+		Tag = mStringPropertyData.Alloc(def);
+	}
+}
+
 
 void AActor::ClearCounters()
 {
diff --git a/src/thingdef/thingdef_properties.cpp b/src/thingdef/thingdef_properties.cpp
index f7221c435..efff2b665 100644
--- a/src/thingdef/thingdef_properties.cpp
+++ b/src/thingdef/thingdef_properties.cpp
@@ -299,7 +299,7 @@ DEFINE_PROPERTY(skip_super, 0, Actor)
 DEFINE_PROPERTY(tag, S, Actor)
 {
 	PROP_STRING_PARM(str, 0);
-	defaults->Tag = str;
+	defaults->SetTag(str);
 }
 
 //==========================================================================
diff --git a/src/version.h b/src/version.h
index 5edcb7108..bb2e096ac 100644
--- a/src/version.h
+++ b/src/version.h
@@ -75,7 +75,7 @@
 // SAVESIG should match SAVEVER.
 
 // MINSAVEVER is the minimum level snapshot version that can be loaded.
-#define MINSAVEVER 3085
+#define MINSAVEVER 3100
 
 #if SVN_REVISION_NUMBER < MINSAVEVER
 // If we don't know the current revision write something very high to ensure that