The VMware Virtual Disk Manager (vdiskmanager) is a handy command line tool that will allow you to expand the size of a vmware virtual disk, and many other things. For more information about using the vdiskmanager command visit the VMware Server Online Library. [more]

VMware Virtual Disk Manager - build 59824.
Usage: vmware-vdiskmanager.exe OPTIONS <disk-name> | <mount-point>
Offline disk manipulation utility
  Options:
     -c                   : create disk; need to specify other create options
     -d                   : defragment the specified virtual disk
     -k                   : shrink the specified virtual disk
     -n <source-disk>     : rename the specified virtual disk; need to
                            specify destination disk-name
     -p                   : prepare the mounted virtual disk specified by
                            the drive-letter for shrinking
     -q                   : do not log messages
     -r <source-disk>     : convert the specified disk; need to specify
                            destination disk-type
     -x <new-capacity>    : expand the disk to the specified capacity

     Additional options for create and convert:
        -a <adapter>      : (for use with -c only) adapter type (ide, buslogic or lsilogic)
        -s <size>         : capacity of the virtual disk
        -t <disk-type>    : disk type id

     Disk types:
        0                 : single growable virtual disk
        1                 : growable virtual disk split in 2Gb files
        2                 : preallocated virtual disk
        3                 : preallocated virtual disk split in 2Gb files

     The capacity can be specified in sectors, Kb, Mb or Gb.
     The acceptable ranges:
                           ide adapter : [100.0Mb, 950.0Gb]
                           scsi adapter: [100.0Mb, 950.0Gb]
        ex 1: vmware-vdiskmanager.exe -c -s 850Mb -a ide -t 0 myIdeDisk.vmdk
        ex 2: vmware-vdiskmanager.exe -d myDisk.vmdk
        ex 3: vmware-vdiskmanager.exe -r sourceDisk.vmdk -t 0 destinationDisk.vmdk
        ex 4: vmware-vdiskmanager.exe -x 36Gb myDisk.vmdk
        ex 5: vmware-vdiskmanager.exe -n sourceName.vmdk destinationName.vmdk
        ex 6: vmware-vdiskmanager.exe -k myDisk.vmdk
        ex 7: vmware-vdiskmanager.exe -p <mount-point>
              (A virtual disk first needs to be mounted at <mount-point>)