debian:/var/vm/IRC# vmware-vdiskmanager -x 4GB IRC.vmdk
Using log file /tmp/vmware-root/vdiskmanager.log
  Grow: 100% done.
The old geometry C/H/S of the disk is: 4161/16/63
The new geometry C/H/S of the disk is: 8322/16/63
Disk expansion completed successfully.

WARNING: If the virtual disk is partitioned, you must use a third-party
         utility in the virtual machine to expand the size of the
         partitions. For more information, see:
         http://www.vmware.com/support/kb/enduser/std_adp.php?p_faqid=1647
debian:/var/vm/IRC#