Index: src/main/java/org/exolab/castor/xml/schema/ElementDecl.java
===================================================================
--- src/main/java/org/exolab/castor/xml/schema/ElementDecl.java	(Revision 6895)
+++ src/main/java/org/exolab/castor/xml/schema/ElementDecl.java	(Arbeitskopie)
@@ -798,11 +798,11 @@
         //--do you really allow parent to be null???
         if (getParent() != null) {
             if (getParent().getStructureType() == Structure.SCHEMA) {
-                if (getMinOccurs() > 1) {
+                if (isMinOccursSet()) {
                     String err = "'minOccurs' declaration is prohibited on top level element.";
                     throw new ValidationException(err);
                 }
-                if ((getMaxOccurs() >1) || (getMaxOccurs() < 0) ) {
+                if (isMaxOccursSet()) {
                     String err = "'maxOccurs' declaration is prohibited on top level element.";
                     throw new ValidationException(err);
                 }
Index: src/main/java/org/exolab/castor/xml/schema/Particle.java
===================================================================
--- src/main/java/org/exolab/castor/xml/schema/Particle.java	(Revision 6895)
+++ src/main/java/org/exolab/castor/xml/schema/Particle.java	(Arbeitskopie)
@@ -62,6 +62,11 @@
      * The maximum occurance
     **/
     private int _maxOccurs = 1;
+    
+    /**
+     * Indicates whether maxOccurs has been set.
+     */
+    private boolean _maxOccursSet = false;
 
     /**
      * The minimum occurance
@@ -69,6 +74,11 @@
     private int _minOccurs  = 1;
 
     /**
+     * Indicates whether minOccurs has been set.
+     */
+    private boolean _minOccursSet = false;
+
+    /**
      * A constant to represent an UNBOUNDED particle
      */
      public static int UNBOUNDED = -1;
@@ -90,7 +100,9 @@
     protected Particle(int minOccurs, int maxOccurs) {
         super();
         setMinOccurs(minOccurs);
+        _minOccursSet = true;
         setMaxOccurs(maxOccurs);
+        _maxOccursSet = true;
     } //-- Particle
 
     /**
@@ -124,6 +136,7 @@
     **/
     public final void setMaxOccurs(int maxOccurs) {
         _maxOccurs = maxOccurs;
+        _maxOccursSet = true;
     } //-- setMaxOccurs
 
     /**
@@ -135,6 +148,7 @@
     **/
     public final void setMinOccurs(int minOccurs) {
         _minOccurs = minOccurs;
+        _minOccursSet = true;
     } //-- setMinOccurs
 
     /**
@@ -148,5 +162,21 @@
       }
       return false;
     }
+    
+    /**
+     * Indicates whetehr maxOccurs has been set.
+     * @return True if maxOccurs has been set.
+     */
+    public final boolean isMaxOccursSet() {
+        return _maxOccursSet;
+    }
 
+    /**
+     * Indicates whether minOccurs has been set.
+     * @return True if minOccurs has been set. 
+     */
+    public final boolean isMinOccursSet() {
+        return _maxOccursSet;
+    }
+
 } //-- CMParticle
\ Kein Zeilenvorschub am Ende der Datei
Index: src/main/java/org/exolab/castor/xml/schema/reader/ElementUnmarshaller.java
===================================================================
--- src/main/java/org/exolab/castor/xml/schema/reader/ElementUnmarshaller.java	(Revision 6895)
+++ src/main/java/org/exolab/castor/xml/schema/reader/ElementUnmarshaller.java	(Arbeitskopie)
@@ -113,7 +113,7 @@
      * @param resolver the resolver being used for reference resolving
     **/
     public ElementUnmarshaller
-        (Schema schema, AttributeSet atts, Resolver resolver)
+        (final Schema schema, final AttributeSet atts, final Resolver resolver)
         throws XMLException
     {
         super();
@@ -122,9 +122,9 @@
         this._schema = schema;
 
         _element = new ElementDecl(schema);
-
+        
         String attValue = null;
-
+        
         //-- @ref
         attValue = atts.getValue(SchemaNames.REF_ATTR);
         if (attValue != null) {
Index: codegen/src/main/java/org/exolab/castor/builder/SourceGenerator.java
===================================================================
--- codegen/src/main/java/org/exolab/castor/builder/SourceGenerator.java	(Revision 6895)
+++ codegen/src/main/java/org/exolab/castor/builder/SourceGenerator.java	(Arbeitskopie)
@@ -601,6 +601,13 @@
         }
 
         Schema schema = schemaUnmarshaller.getSchema();
+        
+        try {
+            schema.validate();
+        } catch (ValidationException vx) {
+            throw new NestedIOException(vx);
+        }
+        
         generateSource(schema, packageName);
     } //-- generateSource