Thanks but it didn't work. The file system didn't change in size. What we had to do was something along the lines of delete the partition from inside airwave, recreate the partition, pvresize then lvresize. Only managed to get it wrong once and corrupt the filesystem :-)
[root@airwave mercury]# df -h
Filesystem Size Used Avail Use% Mounted on
/dev/mapper/VolGroup00-LogVol00 124G 74G 45G 63% /
[root@airwave mercury]# fdisk /dev/sda
/dev/sda1 * 2048 206847 102400 83 Linux
/dev/sda2 206848 167772159 83782656 8e Linux LVM
Command (m for help): d
Partition number (1-4): 2
Command (m for help): n
Command action
e extended
p primary partition (1-4)
p
Partition number (1-4): 2
First sector (206848-272629759, default 206848):
Using default value 206848
Last sector, +sectors or +size{K,M,G} (206848-272629759, default 272629759):
Using default value 272629759
Command (m for help): w
REBOOT
pvresize /dev/sda2
lvresize -r -L+XXg /dev/VolGroup00/LogVol00