--- a/serverboot/default_pager.c	2010-05-19 13:36:30.000000000 +0200
+++ b/serverboot/default_pager.c	2010-05-19 13:36:39.000000000 +0200
@@ -1668,7 +1668,7 @@
  * if it is different from <addr>, it must be deallocated after use.
  */
 int
-default_read(ds, addr, size, offset, out_addr, deallocate)
+default_read(ds, addr, size, offset, out_addr, deallocate, external)
 	register dpager_t	ds;
 	vm_offset_t		addr;	/* pointer to block to fill */
 	register vm_size_t	size;
@@ -1676,6 +1676,7 @@
 	vm_offset_t		*out_addr;
 				/* returns pointer to data */
 	boolean_t		deallocate;
+	boolean_t		external;
 {
 	register union dp_map	block;
 	vm_offset_t	raddr;
@@ -1692,8 +1693,18 @@
 	 * Find the block in the paging partition
 	 */
 	block = pager_read_offset(ds, offset);
-	if ( no_block(block) )
+	if ( no_block(block) ) {
+	    if (external) {
+		/* 
+		 * An external object is requesting unswapped data,
+		 * zero fill the page and return.
+		 */ 
+		bzero((char *) addr, vm_page_size);
+		*out_addr = addr;
+		return (PAGER_SUCCESS);
+	    }
 	    return (PAGER_ABSENT);
+	}
 
 	/*
 	 * Read it, trying for the entire page.
@@ -1844,6 +1855,7 @@
 	mach_port_urefs_t request_refs;	/* Request port user-refs */
 	mach_port_t	pager_name;	/* Name port */
 	mach_port_urefs_t name_refs;	/* Name port user-refs */
+	boolean_t	external;	/* Is an external object? */
 
 	unsigned int	readers;	/* Reads in progress */
 	unsigned int	writers;	/* Writes in progress */
@@ -2301,10 +2313,12 @@
 		/* possibly generate an immediate no-senders notification */
 		sync = 0;
 		pset = default_pager_internal_set;
+		ds->external = FALSE;
 	} else {
 		/* delay notification till send right is created */
 		sync = 1;
 		pset = default_pager_external_set;
+		ds->external = TRUE;
 	}
 
 	kr = mach_port_request_notification(default_pager_self, pager,
@@ -2655,7 +2669,8 @@
 	else
 	  rc = default_read(&ds->dpager, dpt->dpt_buffer,
 			    vm_page_size, offset,
-			    &addr, protection_required & VM_PROT_WRITE);
+			    &addr, protection_required & VM_PROT_WRITE,
+			    ds->external);
 
 	switch (rc) {
 	    case PAGER_SUCCESS: