diff --git a/src/org/umlgraph/doclet/ClassGraph.java b/src/org/umlgraph/doclet/ClassGraph.java
index a3676e1..8afe663 100644
--- a/src/org/umlgraph/doclet/ClassGraph.java
+++ b/src/org/umlgraph/doclet/ClassGraph.java
@@ -972,7 +972,7 @@ class ClassGraph {
     private Type[] getInterfaceTypeArguments(ClassDoc iface, Type t) {
 	if (t instanceof ParameterizedType) {
 	    ParameterizedType pt = (ParameterizedType) t;
-	    if (iface.equals(t.asClassDoc())) {
+	    if (iface != null && iface.equals(t.asClassDoc())) {
 		return pt.typeArguments();
 	    } else {
 		for (Type pti : pt.interfaceTypes()) {
diff --git a/src/org/umlgraph/doclet/ClassInfo.java b/src/org/umlgraph/doclet/ClassInfo.java
index 82fac87..887b91e 100644
--- a/src/org/umlgraph/doclet/ClassInfo.java
+++ b/src/org/umlgraph/doclet/ClassInfo.java
@@ -25,7 +25,7 @@ import java.util.List;
 import java.util.Map;
 
 /**
- * Class's dot-comaptible alias name (for fully qualified class names)
+ * Class's dot-compatible alias name (for fully qualified class names)
  * and printed information
  * @version $Revision$
  * @author <a href="http://www.spinellis.gr">Diomidis Spinellis</a>
diff --git a/src/org/umlgraph/doclet/UmlGraphDoc.java b/src/org/umlgraph/doclet/UmlGraphDoc.java
index 6b574e9..81613d1 100644
--- a/src/org/umlgraph/doclet/UmlGraphDoc.java
+++ b/src/org/umlgraph/doclet/UmlGraphDoc.java
@@ -98,7 +98,7 @@ public class UmlGraphDoc {
     	    UmlGraph.buildGraph(root, view, packageDoc);
     	    runGraphviz(opt.dotExecutable, outputFolder, packageDoc.name(), packageDoc.name(), root);
     	    alterHtmlDocs(opt, outputFolder, packageDoc.name(), packageDoc.name(),
-    		    "package-summary.html", Pattern.compile(".*</[Hh]2>.*"), root);
+    		    "package-summary.html", Pattern.compile("(</[Hh]2>)|(<h1 title=\"Package\").*"), root);
 	    }
 	}
     }