asterisk:~/asterisk-1.4.4# ls -la /usr/src
total 40480
drwxrwsr-x  6 root src      4096 2007-06-07 06:46 .
drwxr-xr-x 10 root root     4096 2007-06-06 14:51 ..
lrwxrwxrwx  1 root src        19 2007-06-06 17:12 linux -> linux-source-2.6.18
lrwxrwxrwx  1 root src        19 2007-06-06 17:12 linux-2.6 -> linux-source-2.6.18
drwxr-xr-x 17 root root     4096 2007-06-07 06:46 linux-headers-2.6.18-4
drwxr-xr-x  4 root root     4096 2007-06-07 06:46 linux-headers-2.6.18-4-486
drwxr-xr-x  3 root root     4096 2007-06-07 06:46 linux-kbuild-2.6.18
drwxr-xr-x 19 root root     4096 2007-05-01 15:06 linux-source-2.6.18
-rw-r--r--  1 root root 41380238 2007-05-01 16:54 linux-source-2.6.18.tar.bz2