[Libguestfs] Image Not Expanding

Hello, I am running xen with libvirt. I have an image(Fedora12) with xen para virt and run with the help of libvirt. So i wanted to increase the size of this image from 1GB to 2 GB. I am using virt-resize command for this. When i do : virt-list-partitions it displays 2 partitions 1] /dev/sda1 and 2] /dev/sda2 I want to resize this to 2 gb So i do like this: virt-resize --expand /dev/sda1 Fedora12 Fedora12-1 The command executes successfully but when i start the VM its shows old size of the Parttions. Actually from outside its sda1 partition but sincce it is para virt it show xvda1 after VM boot up which still shows old size. Any Ideas on this ? Thanks Vipul