diff --git a/base/flatten.c b/base/flatten.c
index 3a61b72..14b3b25 100644
--- a/base/flatten.c
+++ b/base/flatten.c
@@ -249,6 +249,7 @@ void flattenCell(char *name, int file)
 int flattenInstancesOf(char *name, int fnum, char *instance)
 {
   struct objlist *ParentParams;
+  struct objlist *ParentProps;
   struct objlist *NextObj;
   struct objlist *ChildObjList;
   struct nlist *ThisCell;
@@ -308,6 +309,14 @@ int flattenInstancesOf(char *name, int fnum, char *instance)
       if (ChildCell->class != CLASS_SUBCKT) continue;
       if (ChildCell == ThisCell) continue;	// Avoid infinite loop
 
+      /* Does the parent cell have properties?  If so, save a pointer to them */
+      for (ParentProps = ParentParams->next; ParentProps &&
+		ParentProps->type != FIRSTPIN;
+		ParentProps = ParentProps->next) {
+	 if (ParentProps->type == PROPERTY) break;
+      }
+      if (ParentProps && (ParentProps->type != PROPERTY)) ParentProps = NULL;
+
       /* not primitive, so need to flatten this instance */
       notdone = 1;
       /* if this is a new instance, flatten it */
@@ -406,7 +415,9 @@ int flattenInstancesOf(char *name, int fnum, char *instance)
       prefixlength = strlen(tmpstr);
 #endif
       for (tmp = ChildObjList; tmp != NULL; tmp = tmp->next) {
-	if (tmp->type == PROPERTY) continue;
+	if (tmp->type == PROPERTY)
+	    continue;
+
 	else if (IsGlobal(tmp)) {
 	   /* Keep the name but search for node of same name in parent	*/
 	   /* and replace the node number, if found.			*/
@@ -455,6 +466,31 @@ int flattenInstancesOf(char *name, int fnum, char *instance)
 	  HashPtrInstall(tmp->instance.name, tmp, ThisCell->insttab, OBJHASHSIZE);
       }
 
+      /* do property inheritance */
+      if (ParentProps) {
+         for (ob2 = ChildObjList; ob2 != NULL; ob2=ob2->next) {
+
+	    /* If the parent cell has properties to declare, then	*/
+	    /* pass them on to children.				*/
+
+	    if (ob2->type == PROPERTY) {
+		struct valuelist *vl;
+		int i;
+		for (i == 0;; i++) {
+		    vl = &(ob2->instance.props[i]);
+		    if (vl->type == PROP_ENDLIST) break;
+		    else if (vl->type == PROP_EXPRESSION) {
+			/* Only expressions take substitutions */
+			struct tokstack *token;
+			for (token = vl->value.stack; token; token = token->next) {
+			    /* WIP */
+			}
+		    }
+		}
+	    }
+         }
+      }
+
       /* splice instance out of parent */
       if (ParentParams == ThisCell->cell) {
 	/* ParentParams are the very first thing in the list */
@@ -468,6 +504,7 @@ int flattenInstancesOf(char *name, int fnum, char *instance)
 	   for (ob2->next = ChildObjList; ob2->next != NULL; ob2 = ob2->next) ;
       }
       /* now, ob2 is last element in child list, so skip and reclaim parent */
+
       tmp = ParentParams;
       do {
 	tmp = tmp->next;
diff --git a/base/netcmp.c b/base/netcmp.c
index 12b02fd..0dc987c 100644
--- a/base/netcmp.c
+++ b/base/netcmp.c
@@ -3327,8 +3327,8 @@ int PropertyMatch(struct objlist *ob1, struct objlist *ob2, int do_print)
 	    }
 	}
 	if (vl2->type != PROP_ENDLIST) {
-	    if (do_print) Fprintf(stdout, "Circuit 2 %s instance %s does not"
-			" define required properties.\n",
+	    if (do_print) Fprintf(stdout, "Circuit 2 %s instance %s missing"
+			" required properties.\n",
 			Circuit2->name, ob2->instance.name);
 	    return -1;
 	}
@@ -3352,8 +3352,8 @@ int PropertyMatch(struct objlist *ob1, struct objlist *ob2, int do_print)
 	    }
 	}
 	if (vl1->type != PROP_ENDLIST) {
-	    if (do_print) Fprintf(stdout, "Circuit 1 %s instance %s does not"
-			" define required properties.\n",
+	    if (do_print) Fprintf(stdout, "Circuit 1 %s instance %s missing"
+			" required properties.\n",
 			Circuit1->name, ob1->instance.name);
 	    return -1;
 	}
@@ -3389,6 +3389,14 @@ int PropertyMatch(struct objlist *ob1, struct objlist *ob2, int do_print)
       kl2 = (struct property *)HashLookup(vl2->key, tc2->proptab, OBJHASHSIZE);
       if (kl2 == NULL) continue;
 
+      /* Watch out for uninitialized entries in cell def */
+      if (vl1->type == vl2->type) {
+	 if (kl1->type == PROP_STRING && kl1->pdefault.string == NULL)
+	    SetPropertyDefault(kl1, vl1);
+	 if (kl2->type == PROP_STRING && kl2->pdefault.string == NULL)
+	    SetPropertyDefault(kl2, vl2);
+      }
+
       if (vl1->type != vl2->type) {
 	 if (kl1->type != vl1->type) PromoteProperty(kl1, vl1);
 	 if (kl2->type != vl2->type) PromoteProperty(kl2, vl2);
diff --git a/base/netgen.c b/base/netgen.c
index 9558019..0eef7e3 100644
--- a/base/netgen.c
+++ b/base/netgen.c
@@ -193,28 +193,27 @@ int TokGetValue(char *estr, struct nlist *parent, int glob, double *dval)
 				spiceparams, OBJHASHSIZE);
 	    if (kl != NULL) {
 		result = ConvertStringToFloat(kl->pdefault.string, dval);
+		return ((result == 0) ? -1 : 1);
 	    }
 	}
     }
-    else {
-	/* Check local parameters */
-	kl = (struct property *)HashLookup(estr,
-				parent->proptab, OBJHASHSIZE);
-	if (kl != NULL) {
-	    switch(kl->type) {
-		case PROP_STRING:
-		    result = ConvertStringToFloat(kl->pdefault.string, dval);
-		    break;
-		case PROP_DOUBLE:
-		case PROP_VALUE:
-		    *dval = kl->pdefault.dval;
-		    result = 1;
-		    break;
-		case PROP_INTEGER:
-		    *dval = (double)kl->pdefault.ival;
-		    result = 1;
-		    break;
-	    }
+
+    /* Check local parameters */
+    kl = (struct property *)HashLookup(estr, parent->proptab, OBJHASHSIZE);
+    if (kl != NULL) {
+	switch(kl->type) {
+	    case PROP_STRING:
+		result = ConvertStringToFloat(kl->pdefault.string, dval);
+		break;
+	    case PROP_DOUBLE:
+	    case PROP_VALUE:
+		*dval = kl->pdefault.dval;
+		result = 1;
+		break;
+	    case PROP_INTEGER:
+		*dval = (double)kl->pdefault.ival;
+		result = 1;
+		break;
 	}
     }
     return ((result == 0) ? -1 : 1);
@@ -1924,10 +1923,6 @@ void DeleteProperties(struct keyvalue **topptr)
 /* to relate them to the cell that is being instanced.  Because this	*/
 /* is used to link the same properties multiple times for parallel	*/
 /* devices, copy the list (a refcount would work better. . .)		*/
-/*									*/
-/* If "isdefault" is "true", then the record is installed in the	*/
-/* object hash under the name "defaults";  otherwise, it gets the	*/
-/* name "properties" and is not added to the object hash.		*/
 /*----------------------------------------------------------------------*/
 
 struct objlist *LinkProperties(char *model, struct keyvalue *topptr)
@@ -1953,10 +1948,6 @@ struct objlist *LinkProperties(char *model, struct keyvalue *topptr)
 	return NULL;
     }
     cell = LookupCellFile(model, filenum);
-    if (cell == NULL) {
-	Printf("No cell '%s' found to link properties to.\n", model);
-	return NULL;
-    }
 
     tp = GetObject();
     tp->type = PROPERTY;
@@ -1977,6 +1968,27 @@ struct objlist *LinkProperties(char *model, struct keyvalue *topptr)
 	/* No promotion to types other than string at this point */
 	newkv->type = PROP_STRING;
 	newkv->value.string = strsave(kv->value);
+
+	if (cell != NULL) {
+	    struct property *kl = NULL;
+
+	    /* If there is a matching cell, make sure that the property */
+	    /* key exists.  If not, create it and flag a warning.	*/
+
+	    kl = (struct property *)HashLookup(newkv->key, cell->proptab, OBJHASHSIZE);
+	    if (kl == NULL) {
+		Fprintf(stderr, "Warning:  Property %s passed to cell %s which "
+			"does not define a default.\n",
+			newkv->key, cell->name);
+		kl = NewProperty();
+		kl->key = strsave(newkv->key);
+		kl->idx = 0;
+		kl->type = PROP_STRING;
+		kl->slop.ival = 0;
+		kl->pdefault.string = NULL;
+		HashPtrInstall(kl->key, kl, cell->proptab, OBJHASHSIZE);
+	    }
+	}
     }
 
     /* Final entry marks the end of the list */
@@ -1989,6 +2001,40 @@ struct objlist *LinkProperties(char *model, struct keyvalue *topptr)
     return tp;
 }
 
+/*----------------------------------------------------------------------*/
+/* SetPropertyDefault() ---						*/
+/*									*/
+/* If a cell does not set property defaults, but an instance of that	*/
+/* cell passes a property to it, then there will be a default value	*/
+/* with a string type and a NULL value.  Set the default to be equal	*/
+/* to the instance type and value.					*/
+/*----------------------------------------------------------------------*/
+
+int SetPropertyDefault(struct property *prop, struct valuelist *vl)
+{
+    if (prop == NULL || vl == NULL) return -1;
+    if (prop->type != PROP_STRING || prop->pdefault.string != NULL) return 1;
+
+    prop->type = vl->type;
+
+    switch (vl->type) {
+	case PROP_STRING:
+	    prop->pdefault.string = strsave(vl->value.string);
+	    break;
+	case PROP_INTEGER:
+	    prop->pdefault.ival = vl->value.ival;
+	    break;
+	case PROP_DOUBLE:
+	case PROP_VALUE:
+	    prop->pdefault.dval = vl->value.dval;
+	    break;
+	case PROP_EXPRESSION:
+	    prop->pdefault.stack = CopyTokStack(vl->value.stack);
+	    break;
+    }
+    return 1;
+}
+
 /*----------------------------------------------------------------------*/
 /* PromoteProperty() ---						*/
 /*									*/
diff --git a/base/netgen.h b/base/netgen.h
index 9d6ea5a..58312ec 100644
--- a/base/netgen.h
+++ b/base/netgen.h
@@ -40,6 +40,7 @@ extern int  PropertyTolerance(char *name, int fnum, char *key, int ival,
 extern void ResolveProperties(char *name1, int file1, char *name2, int file2);
 extern void CopyProperties(struct objlist *obj_to, struct objlist *obj_from);
 extern int PromoteProperty(struct property *, struct valuelist *);
+extern int SetPropertyDefault(struct property *, struct valuelist *);
 extern struct objlist *LinkProperties(char *model, struct keyvalue *topptr);
 extern int ReduceExpressions(struct objlist *instprop, struct nlist *parent,
 		int glob);
diff --git a/base/spice.c b/base/spice.c
index 88136ec..d5de1c6 100644
--- a/base/spice.c
+++ b/base/spice.c
@@ -903,9 +903,9 @@ skip_ends:
 	    if (!strcasecmp(nexttok, "M"))
 		sscanf(eqptr + 1, "%d", &ndev);
 	    else if (!strcasecmp(nexttok, "L"))
-		AddProperty(&kvlist, "length", eqptr + 1);
+		AddProperty(&kvlist, "L", eqptr + 1);
 	    else if (!strcasecmp(nexttok, "W"))
-		AddProperty(&kvlist, "width", eqptr + 1);
+		AddProperty(&kvlist, "W", eqptr + 1);
 	    else 
 		AddProperty(&kvlist, nexttok, eqptr + 1);
 	 }
diff --git a/tcltk/tclnetgen.c b/tcltk/tclnetgen.c
index 5991ab0..ff8ff5a 100644
--- a/tcltk/tclnetgen.c
+++ b/tcltk/tclnetgen.c
@@ -3206,11 +3206,16 @@ _netcmp_property(ClientData clientData,
 			if (result != TCL_OK) return result;
 
 			result = Tcl_GetIntFromObj(interp, tobj2, &ival);
-			if (result != TCL_OK) Tcl_ResetResult(interp);
-			if ((result = Tcl_GetDoubleFromObj(interp, tobj2, &dval))
-				!= TCL_OK)
-			    return result;
-
+			if (result != TCL_OK) {
+			    Tcl_ResetResult(interp);
+			    if (!strncasecmp(Tcl_GetString(tobj2), "inf", 3)) {
+				ival = 1<<30;
+				dval = 1.0E+300;
+			    }
+			    else if ((result = Tcl_GetDoubleFromObj(interp, tobj2, &dval))
+					!= TCL_OK)
+				return result;
+			}
 			PropertyTolerance(tp->name, fnum, Tcl_GetString(tobj1),
 					ival, dval);
 		    }