root@ks311469:/usr/src/asterisk/dahdi-linux-complete-2.6.0+2.6.0# apt-get install linux-headers
Reading package lists... Done
Building dependency tree
Reading state information... Done
Package linux-headers is a virtual package provided by:
  linux-headers-2.6.31-11-rt 2.6.31-11.154
  linux-headers-2.6.32-38-server 2.6.32-38.83
  linux-headers-2.6.32-38-preempt 2.6.32-38.83
  linux-headers-2.6.32-38-generic 2.6.32-38.83
  linux-headers-2.6.32-38 2.6.32-38.83
  linux-headers-2.6.32-37-server 2.6.32-37.81
  linux-headers-2.6.32-37-preempt 2.6.32-37.81
  linux-headers-2.6.32-37-generic 2.6.32-37.81
  linux-headers-2.6.32-37 2.6.32-37.81
  linux-headers-2.6.32-36-server 2.6.32-36.79
  linux-headers-2.6.32-36-preempt 2.6.32-36.79
  linux-headers-2.6.32-36-generic 2.6.32-36.79
  linux-headers-2.6.32-36 2.6.32-36.79
  linux-headers-2.6.32-35-server 2.6.32-35.78
  linux-headers-2.6.32-35-preempt 2.6.32-35.78
  linux-headers-2.6.32-35-generic 2.6.32-35.78
  linux-headers-2.6.32-35 2.6.32-35.78
  linux-headers-2.6.32-34-server 2.6.32-34.77
  linux-headers-2.6.32-34-preempt 2.6.32-34.77
  linux-headers-2.6.32-34-generic 2.6.32-34.77
  linux-headers-2.6.32-34 2.6.32-34.77
  linux-headers-2.6.32-33-server 2.6.32-33.72
  linux-headers-2.6.32-33-preempt 2.6.32-33.72
  linux-headers-2.6.32-33-generic 2.6.32-33.72
  linux-headers-2.6.32-33 2.6.32-33.72
  linux-headers-2.6.32-32-server 2.6.32-32.62
  linux-headers-2.6.32-32-preempt 2.6.32-32.62
  linux-headers-2.6.32-32-generic 2.6.32-32.62
  linux-headers-2.6.32-32 2.6.32-32.62
  linux-headers-2.6.32-31-server 2.6.32-31.61
  linux-headers-2.6.32-31-preempt 2.6.32-31.61
  linux-headers-2.6.32-31-generic 2.6.32-31.61
  linux-headers-2.6.32-31 2.6.32-31.61
  linux-headers-2.6.32-30-server 2.6.32-30.59
  linux-headers-2.6.32-30-preempt 2.6.32-30.59
  linux-headers-2.6.32-30-generic 2.6.32-30.59
  linux-headers-2.6.32-30 2.6.32-30.59
  linux-headers-2.6.32-29-server 2.6.32-29.58
  linux-headers-2.6.32-29-preempt 2.6.32-29.58
  linux-headers-2.6.32-29-generic 2.6.32-29.58
  linux-headers-2.6.32-29 2.6.32-29.58
  linux-headers-2.6.32-28-server 2.6.32-28.55
  linux-headers-2.6.32-28-preempt 2.6.32-28.55
  linux-headers-2.6.32-28-generic 2.6.32-28.55
  linux-headers-2.6.32-28 2.6.32-28.55
  linux-headers-2.6.32-27-server 2.6.32-27.49
  linux-headers-2.6.32-27-preempt 2.6.32-27.49
  linux-headers-2.6.32-27-generic 2.6.32-27.49
  linux-headers-2.6.32-27 2.6.32-27.49
  linux-headers-2.6.32-26-server 2.6.32-26.48
  linux-headers-2.6.32-26-preempt 2.6.32-26.48
  linux-headers-2.6.32-26-generic 2.6.32-26.48
  linux-headers-2.6.32-26 2.6.32-26.48
  linux-headers-2.6.32-25-server 2.6.32-25.45
  linux-headers-2.6.32-25-preempt 2.6.32-25.45
  linux-headers-2.6.32-25-generic 2.6.32-25.45
  linux-headers-2.6.32-25 2.6.32-25.45
  linux-headers-2.6.32-24-server 2.6.32-24.43
  linux-headers-2.6.32-24-preempt 2.6.32-24.43
  linux-headers-2.6.32-24-generic 2.6.32-24.43
  linux-headers-2.6.32-24 2.6.32-24.43
  linux-headers-2.6.32-23-server 2.6.32-23.37
  linux-headers-2.6.32-23-preempt 2.6.32-23.37
  linux-headers-2.6.32-23-generic 2.6.32-23.37
  linux-headers-2.6.32-23 2.6.32-23.37
  linux-headers-2.6.32-22-server 2.6.32-22.36
  linux-headers-2.6.32-22-preempt 2.6.32-22.36
  linux-headers-2.6.32-22-generic 2.6.32-22.36
  linux-headers-2.6.32-22 2.6.32-22.36
  linux-headers-2.6.31-10-rt 2.6.31-10.153
  linux-headers-2.6.32-21-server 2.6.32-21.32
  linux-headers-2.6.32-21-preempt 2.6.32-21.32
  linux-headers-2.6.32-21-generic 2.6.32-21.32
  linux-headers-2.6.32-21 2.6.32-21.32
You should explicitly select one to install.
E: Package linux-headers has no installation candidate
root@ks311469:/usr/src/asterisk/dahdi-linux-complete-2.6.0+2.6.0# uname -a
Linux ks311469.kimsufi.com 2.6.38.2-grsec-xxxx-grs-ipv6-64 #2 SMP Thu Aug 25 16:40:22 UTC 2011 x86_64 GNU/Linux
root@ks311469:/usr/src/asterisk/dahdi-linux-complete-2.6.0+2.6.0# uname -r
2.6.38.2-grsec-xxxx-grs-ipv6-64