How do I create a volume withing an extended partiton?

[Dave Martini 1]

I have 3 partitions on my boot disk and went into fdisk utility and
made an extended partition for the rest of the free space on the disk.

Command (m for help): p

Disk /dev/sda: 73.4 GB, 73407865856 bytes
255 heads, 63 sectors/track, 8924 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes

   Device Boot    Start       End    Blocks   Id  System
/dev/sda1   *         1       127   1020096   83  Linux
/dev/sda2           128       382   2048287+  82  Linux swap
/dev/sda3           383      1657  10241437+  83  Linux
/dev/sda4          1658      8924  58372177+   5  Extended

Command (m for help): 


How do I make and mount volumes on my system within this extended 
area?

I can't do a mkfs on the sda4 extended slice

# mkfs -t ext3 /dev/sda4
mke2fs 1.32 (09-Nov-2002)
mkfs.ext3: No such device or address while trying to determine filesystem size
[root at erdlx1 root]# 

I've done this on the initial install of the OS and made many extended
partitions but haven't ever done it after the fact using fdisk.

Any help on how to use this extended space to create volumes and mount
them would be great.
Dave Martini
LLNL