diff -r ab576c51e77c -r dd74a80a34d6 src/net/lemnik/eodsql/spi/Context.java
--- a/src/net/lemnik/eodsql/spi/Context.java	Sun Sep 19 22:06:50 2010 +0200
+++ b/src/net/lemnik/eodsql/spi/Context.java	Fri Oct 29 21:13:08 2010 +0200
@@ -53,6 +53,8 @@
     private boolean dontCloseConnection = false;
 
     private boolean closed = false;
+    
+    private final boolean childContext;
 
     /**
      * <p>
@@ -75,6 +77,7 @@
         this.parameters = parameters != null
                 ? parameters
                 : EMPTY_PARAMETERS;
+        this.childContext = false;
     }
 
     /**
@@ -82,8 +85,13 @@
      * {@code Context} with new parameters. This constructor will copy
      * the annotation and all of the current resources from the
      * {@code parentContext} into itself. Resources added to the parent
-     * context after this construction will not affect the new {@code Context},
-     * and vice-versa.
+     * context after this construction will not affect the new {@code Context}.
+     * <p>
+     * This context is read-only. Calling {@link #setResource(Resource)} will throw an 
+     * {@link IllegalStateException}. Calling {@link #close()} on this context is a no-op, i.e.
+     * no resources will be freed when calling this. It is the responsibility of the parent context
+     * to free the resources. 
+     * </p> 
      *
      * @param parentContext the context to copy the state from
      * @param newParameters the new parameters
@@ -108,6 +116,7 @@
         this.resources.putAll(parentContext.resources);
         this.parameters = newParameters;
         this.autoclose = parentContext.autoclose;
+        this.childContext = true;
     }
 
     @Override
@@ -176,6 +185,10 @@
      * @param resource the {@code Resource} to place into this {@code Context}
      */
     public void setResource(final Resource<?> resource) {
+        if (childContext)
+        {
+            throw new IllegalStateException("Cannot add resource to nested context");
+        }
         resources.put(resource.getResourceType(), resource);
     }
 
@@ -259,7 +272,7 @@
      * @see #getResource(java.lang.Class) 
      */
     public void close() throws SQLException {
-        if(!closed) {
+        if(!closed && !childContext) {
             closed = true;
 
             // we want to iterate through the values in reverse