diff --git a/VERSION b/VERSION
index 7f3bad14..236cf05e 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-8.3.260
+8.3.261
diff --git a/calma/CalmaRdcl.c b/calma/CalmaRdcl.c
index 0048db80..a64e0aeb 100644
--- a/calma/CalmaRdcl.c
+++ b/calma/CalmaRdcl.c
@@ -400,7 +400,11 @@ calmaParseStructure(filename)
 	if (CalmaDateStamp == NULL)
 	    cifReadCellDef->cd_timestamp = timestampval;
 	else
+	{
 	    cifReadCellDef->cd_timestamp = *CalmaDateStamp;
+	    if (*CalmaDateStamp != (time_t)0)
+		cifReadCellDef->cd_flags |= CDFIXEDSTAMP;
+	}
 
 	/* For read-only cells, set flag in def */
 	if (CalmaReadOnly)
diff --git a/commands/CmdCD.c b/commands/CmdCD.c
index f2e47610..7b6862e5 100644
--- a/commands/CmdCD.c
+++ b/commands/CmdCD.c
@@ -1378,11 +1378,20 @@ CmdCellname(w, cmd)
 	    }
 	    else if (locargc == 4 || (locargc == 3 && cellname == NULL))
 	    {
-		int timestamp = atoi(cmd->tx_argv[2 + ((cellname == NULL) ? 0 : 1)]);
-		if (timestamp != cellDef->cd_timestamp)
+		int timestamp;
+		if (StrIsInt(cmd->tx_argv[2 + ((cellname == NULL) ? 0 : 1)]))
 		{
-		    cellDef->cd_timestamp = timestamp;
-		    cellDef->cd_flags &= ~CDGETNEWSTAMP;
+		    timestamp = atoi(cmd->tx_argv[2 + ((cellname == NULL) ? 0 : 1)]);
+		    if (timestamp != cellDef->cd_timestamp)
+		    {
+			cellDef->cd_timestamp = timestamp;
+			cellDef->cd_flags &= ~CDGETNEWSTAMP | CDFIXEDSTAMP;
+		    }
+		}
+		else
+		{
+		    TxError("Invalid timestamp \"%s\".\n",
+			cmd->tx_argv[2 + ((cellname == NULL) ? 0 : 1)]);
 		}
 	    }
 	    break;
@@ -1398,12 +1407,46 @@ CmdCellname(w, cmd)
 		break;
 	    }
 #ifdef MAGIC_WRAPPER
+	    /* All of the flags are included for completeness.  A number
+	     * of these flags are set in self-contained routines and will
+	     * never appear as the result of the "cellname flags" command.
+	     * Mainly for diagnostics (in case a routine is not cleaning
+	     * up its own flag settings, for example).
+	     */
 	    if (cellDef->cd_flags & CDAVAILABLE)
 		Tcl_AppendElement(magicinterp, "available");
 	    if (cellDef->cd_flags & CDMODIFIED)
 		Tcl_AppendElement(magicinterp, "modified");
 	    if (cellDef->cd_flags & CDNOEDIT)
 		Tcl_AppendElement(magicinterp, "readonly");
+	    if (cellDef->cd_flags & CDINTERNAL)
+		Tcl_AppendElement(magicinterp, "internal");
+	    if (cellDef->cd_flags & CDFIXEDSTAMP)
+		Tcl_AppendElement(magicinterp, "fixed-timestamp");
+	    if (cellDef->cd_flags & CDGETNEWSTAMP)
+		Tcl_AppendElement(magicinterp, "timestamp-pending");
+	    if (cellDef->cd_flags & CDSTAMPSCHANGED)
+		Tcl_AppendElement(magicinterp, "child-timestamp-changed");
+	    if (cellDef->cd_flags & CDFIXEDBBOX)
+		Tcl_AppendElement(magicinterp, "fixed-bbox");
+	    if (cellDef->cd_flags & CDBOXESCHANGED)
+		Tcl_AppendElement(magicinterp, "bbox-changed");
+	    if (cellDef->cd_flags & CDPROCESSED)
+		Tcl_AppendElement(magicinterp, "bbox-processed");
+	    if (cellDef->cd_flags & CDFLATGDS)
+		Tcl_AppendElement(magicinterp, "flat-gds");
+	    if (cellDef->cd_flags & CDFLATTENED)
+		Tcl_AppendElement(magicinterp, "flattened-gds");
+	    if (cellDef->cd_flags & CDPROCESSEDGDS)
+		Tcl_AppendElement(magicinterp, "processed-gds");
+	    if (cellDef->cd_flags & CDVENDORGDS)
+		Tcl_AppendElement(magicinterp, "vendor-gds");
+	    if (cellDef->cd_flags & CDVISITED)
+		Tcl_AppendElement(magicinterp, "visited");
+	    if (cellDef->cd_flags & CDDEREFERENCE)
+		Tcl_AppendElement(magicinterp, "dereference");
+	    if (cellDef->cd_flags & CDNOTFOUND)
+		Tcl_AppendElement(magicinterp, "not-found");
 #else
 	    TxPrintf("Flag settings for cell %s:\n", cellname);
 	    TxPrintf("in database: %s\n", (cellDef->cd_flags & CDAVAILABLE) ?
@@ -1412,6 +1455,12 @@ CmdCellname(w, cmd)
 			"true" : "false");
 	    TxPrintf("readonly: %s\n", (cellDef->cd_flags & CDNOEDIT) ?
 			"true" : "false");
+	    TxPrintf("vendor: %s\n", (cellDef->cd_flags & CDVENDORGDS) ?
+			"true" : "false");
+	    TxPrintf("fixed-bbox: %s\n", (cellDef->cd_flags & CDFIXEDBBOX) ?
+			"true" : "false");
+	    TxPrintf("fixed-timestamp: %s\n", (cellDef->cd_flags & CDFIXEDSTAMP) ?
+			"true" : "false");
 #endif
 	    break;
 	case IDX_RENAME:
diff --git a/commands/CmdTZ.c b/commands/CmdTZ.c
index a39e5d8e..3689c735 100644
--- a/commands/CmdTZ.c
+++ b/commands/CmdTZ.c
@@ -1809,7 +1809,6 @@ CmdWire(w, cmd)
 
 #define OPT_WRITEALL_FORCE	0
 #define OPT_WRITEALL_MODIFIED	1
-#define OPT_WRITEALL_NOUPDATE	2	
 
 void
 CmdWriteall(w, cmd)
@@ -1818,7 +1817,7 @@ CmdWriteall(w, cmd)
 {
     int cmdWriteallFunc();
     int option = -1;
-    static char *writeallOpts[] = { "force", "modified", "noupdate", 0 };
+    static char *writeallOpts[] = { "force", "modified", 0 };
     int argc;
     int flags = CDMODIFIED | CDBOXESCHANGED | CDSTAMPSCHANGED;
 
@@ -1848,15 +1847,13 @@ CmdWriteall(w, cmd)
 		    TxError("No such cell \"%s\".\n", cmd->tx_argv[i]);
 		    notfound++;
 		}
-		else if (option != OPT_WRITEALL_NOUPDATE)
-		    DBUpdateStamps(def);
+		DBUpdateStamps(def);
 	    }
 	    if (notfound == cmd->tx_argc - 2) return;
 	}
     }
-    if (option != OPT_WRITEALL_NOUPDATE)
-	if (cmd->tx_argc <= 2)
-	    DBUpdateStamps(NULL);
+    if (cmd->tx_argc <= 2)
+	DBUpdateStamps(NULL);
 
     argc = cmd->tx_argc;
     (void) DBCellSrDefs(flags, cmdWriteallFunc, (ClientData)cmd);
diff --git a/database/DBtimestmp.c b/database/DBtimestmp.c
index 4cbe9c6b..121e074d 100644
--- a/database/DBtimestmp.c
+++ b/database/DBtimestmp.c
@@ -214,11 +214,18 @@ DBUpdateStamps(def)
     extern time_t time();
 
     DBFixMismatch();
+
     timestamp = time((time_t *) 0);
     if (def == NULL)
 	(void) DBCellSrDefs(CDGETNEWSTAMP, dbStampFunc, (ClientData) NULL);
+
     else if (def->cd_flags & CDGETNEWSTAMP)
-	dbStampFunc(def);
+    {
+	if (def->cd_flags & CDFIXEDSTAMP)
+	    def->cd_flags &= ~CDGETNEWSTAMP;
+	else
+	    dbStampFunc(def);
+    }
 }
 
 int
@@ -234,11 +241,12 @@ dbStampFunc(cellDef)
 
     if (cellDef->cd_timestamp == timestamp) return 0;
 
-    cellDef->cd_timestamp = timestamp;
+    if (!(cellDef->cd_flags & CDFIXEDSTAMP))
+	cellDef->cd_timestamp = timestamp;
+
     cellDef->cd_flags &= ~CDGETNEWSTAMP;
 
-    /* printf("Writing new timestamp %d for %s.\n",
-	timestamp, cellDef->cd_name); */
+    // printf("Writing new timestamp %d for %s.\n", timestamp, cellDef->cd_name);
 
     /* If a child's stamp has changed, then the stamps must change
      * in all its parents too.  When the hierarchical DRC becomes
diff --git a/database/database.h.in b/database/database.h.in
index a4556395..50b53d91 100644
--- a/database/database.h.in
+++ b/database/database.h.in
@@ -411,24 +411,30 @@ typedef struct celldef
  *	CDDEREFERENCE is a flag indicating that when loading or expanding
  *	    children of a cell, the path should be ignored and the cell
  *	    path should be searched for the location.
+ *	CDFIXEDSTAMP is a flag indicating that the cell has a fixed
+ *	    timestamp that should not be modified.  This should be used
+ *	    with caution as it messes with the usual timestamp tracking,
+ *	    but is useful for preparing libraries all cells of which have
+ *	    the same timestamp value.
  */
 
-#define	CDAVAILABLE	 0x0001
-#define	CDMODIFIED	 0x0002
-#define	CDNOTFOUND	 0x0004
-#define CDINTERNAL	 0x0008
-#define CDGETNEWSTAMP	 0x0010
-#define CDSTAMPSCHANGED	 0x0020
-#define CDBOXESCHANGED	 0x0040
-#define CDFIXEDBBOX	 0x0080
-#define CDNOEDIT	 0x0100
-#define CDPROCESSED	 0x0200
-#define CDFLATGDS	 0x0400
-#define CDFLATTENED	 0x0800
-#define CDPROCESSEDGDS	 0x1000
-#define CDVENDORGDS	 0x2000
-#define CDVISITED	 0x4000
-#define CDDEREFERENCE	 0x8000
+#define	CDAVAILABLE	 0x00001
+#define	CDMODIFIED	 0x00002
+#define	CDNOTFOUND	 0x00004
+#define CDINTERNAL	 0x00008
+#define CDGETNEWSTAMP	 0x00010
+#define CDSTAMPSCHANGED	 0x00020
+#define CDBOXESCHANGED	 0x00040
+#define CDFIXEDBBOX	 0x00080
+#define CDNOEDIT	 0x00100
+#define CDPROCESSED	 0x00200
+#define CDFLATGDS	 0x00400
+#define CDFLATTENED	 0x00800
+#define CDPROCESSEDGDS	 0x01000
+#define CDVENDORGDS	 0x02000
+#define CDVISITED	 0x04000
+#define CDDEREFERENCE	 0x08000
+#define CDFIXEDSTAMP	 0x10000
 
 /*
  * Description of an array.