when connect to a android phone: device /dev/sdb is not removable

Binary package hint: pmount

$ pmount-hal /dev/sdb
Error: device /dev/sdb is not removable
Error: could not execute pmount

$ lsusb | grep 0bb4
Bus 006 Device 004: ID 0bb4:0c02 High Tech Computer Corp.

$ sudo lsusb -v
[snip]
Bus 006 Device 004: ID 0bb4:0c02 High Tech Computer Corp.
Device Descriptor:
  bLength 18
  bDescriptorType 1
  bcdUSB 1.02
  bDeviceClass 0 (Defined at Interface level)
  bDeviceSubClass 0
  bDeviceProtocol 0
  bMaxPacketSize0 64
  idVendor 0x0bb4 High Tech Computer Corp.
  idProduct 0x0c02
  bcdDevice 1.00
  iManufacturer 3 HTC
  iProduct 2 Android Phone
  iSerial 1 HT*************
  bNumConfigurations 1
  Configuration Descriptor:
    bLength 9
    bDescriptorType 2
    wTotalLength 55
    bNumInterfaces 2
    bConfigurationValue 1
    iConfiguration 0
[snip]

ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 9.04
Package: pmount 0.9.18-2
ProcEnviron:
 PATH=(custom, user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: pmount
Uname: Linux 2.6.28-8-generic x86_64