boot selector and extended partitions

[Mark Davies <mark%ecs.vuw.ac.nz@localhost>]

I'm trying to set up a new laptop to boot either NetBSD or Windows 7.

I've got the following fdisk

Disk: /dev/rsd0d
NetBSD disklabel disk geometry:
cylinders: 16383, heads: 16, sectors/track: 63 (1008 sectors/cylinder)
total sectors: 312581808

BIOS disk geometry:
cylinders: 1024, heads: 255, sectors/track: 63 (16065 sectors/cylinder)
total sectors: 312581808

Partitions aligned to 16065 sector boundaries, offset 63

Partition table:
0: Dell PowerEdge Server utilities (sysid 222)
    start 63, size 433692 (212 MB, Cyls 0-26)
1: NTFS, OS/2 HPFS, QNX2 or Advanced UNIX (sysid 7)
    bootmenu: Windows
    start 434176, size 204800 (100 MB, Cyls 27/6/44-39/197/30), Active
2: NTFS, OS/2 HPFS, QNX2 or Advanced UNIX (sysid 7)
    start 638976, size 41738240 (20380 MB, Cyls 39/197/31-2637/219/14)
3: Ext. partition - LBA (sysid 15)
    start 42377216, size 270200832 (131934 MB, Cyls 
2637/219/15-19457/21/20)
Extended partition table:
E0: Primary DOS with 32 bit FAT (sysid 11)
    start 42379264, size 4194304 (2048 MB, Cyls 2637/251/47-2899/17/62)
E1: NetBSD (sysid 169)
    bootmenu: NetBSD
    start 46573631, size 266004417 (129885 MB, Cyls 
2899/17/63-19457/21/20)
Bootselector enabled, timeout 10 seconds.
First active partition: 1
Drive serial number: 1744830464 (0x68000000)


but if I try and boot I only get a menu comprising
  1. Windows

no NetBSD.  Is this because NetBSD is in an Extended partition?
The manual page does suggest that this should work, what am I missing?
Any suggestions how to make it work properly.

cheers
mark