[CentOS] How to force iscsi to see the new LUN size

Hi,

I increased the size of one of the LUNs and on CentOS 5.4 if I restart 
iscsi (`service iscsi restart`) I'll see the the new size but this will 
disconnect all other LUNs.

I'm hoping that there is isciadm or some other command that will force 
iscsi to rediscover the LUNs but I can't seem to be able to come up with 
one.

Resize2fs says that there is nothing to be done. I'm not using LVM.

Any ideas?

Thanks
Peter