OK, have root on the LG GW620:

1) enable USB Debugging:

Settings -> Applications -> Development -> USB Debugging

2) Install Android SDK

3) Install Android ADB driver for LG USB Modem

4) Enter Hidden Menu on handset: 3845#*620#

5) Module Test -> Stability Test -> Enable Root Permission

6) run adb shell

7) type id:

Code:
C:\android-sdk-windows\tools>adb shell
# id
id
uid=0(root) gid=0(root)
#
8) get init.rc:

Code:

on init

sysclktz 0

loglevel 3

# setup the global environment
    export PATH /sbin:/system/sbin:/system/bin:/system/xbin
    export LD_LIBRARY_PATH /system/lib
    export ANDROID_BOOTLOGO 1
    export ANDROID_ROOT /system
    export ANDROID_ASSETS /system/app
    export ANDROID_DATA /data
    export EXTERNAL_STORAGE /sdcard
    export BOOTCLASSPATH /system/framework/core.jar:/system/framework/ext.jar:/system/framework/framework.jar:/system/framework/android.policy.jar:/system/framework/services.jar

# Backward compatibility
    symlink /system/etc /etc

# create mountpoints and mount tmpfs on sqlite_stmt_journals
    mkdir /sdcard 0077 system system # LGE_CHANGE_S [bluerti@lge.com] 2009-09-18 <Change permission of /sdcard partition as G1/Hero>
    mkdir /system
    mkdir /data 0771 system system
    mkdir /lgdrm 0770 lgdrm lgdrm_acc
    mkdir /cache 0770 system cache
    mkdir /sqlite_stmt_journals 01777 root root
    mount tmpfs tmpfs /sqlite_stmt_journals size=4m

    mount rootfs rootfs / ro remount

    write /proc/sys/kernel/panic_on_oops 1
    write /proc/sys/kernel/hung_task_timeout_secs 0
    write /proc/cpu/alignment 4
    write /proc/sys/kernel/sched_latency_ns 10000000
    write /proc/sys/kernel/sched_wakeup_granularity_ns 2000000

# mount mtd partitions
    # Mount /system rw first to give the filesystem a chance to save a checkpoint
    mount yaffs2 mtd@system /system 
    mount yaffs2 mtd@system /system ro remount

    # We chown/chmod /data again so because mount is run as root + defaults
    mount yaffs2 mtd@userdata /data nosuid nodev
    chown system system /data
    # LGE_CHANGE_S [bluerti@lge.com] 2009-09-18 <Change /data partition as G1/Hero>
    chmod 0771 /data
    
# ricky_kwak@lge.com 2009.08.05
# change init logo image permission
    chmod 0777 /initlogo.rle
    # We chown/chmod mtd0, mtd1 again so because mount is run as root + defaults
    chown system system /dev/mtd/mtd0
    chmod 0777   /dev/mtd/mtd0
    chown system system /dev/mtd/mtd1
    chmod 0777   /dev/mtd/mtd1
    

    # We chown/chmod /lgdrm again so because mount is run as root + defaults
    mount yaffs2 mtd@lgdrm /lgdrm nosuid nodev
    chown lgdrm lgdrm_acc /lgdrm
    chmod 0770 /lgdrm
    
    # Same reason as /data above
    mount yaffs2 mtd@cache /cache nosuid nodev
    chown system cache /cache
    chmod 0770 /cache

    # This may have been created by the recovery system with odd permissions
    chown system system /cache/recovery
    chmod 0770 /cache/recovery


	# LGE_CHANGE_S [bluerti@lge.com] For Factory Reset
	mkdir /data/nv 
	chmod 0777 /data/nv
	# LGE_CHANGE_E
	
# create basic filesystem structure
    mkdir /data/misc 01771 system misc
    mkdir /data/misc/hcid 0770 bluetooth bluetooth
    mkdir /data/local 0771 shell shell
    mkdir /data/local/tmp 0771 shell shell
    mkdir /data/data 0771 system system
    chmod 0771 /data/data
    mkdir /data/app-private 0771 system system
    mkdir /data/app 0771 system system
    mkdir /data/property 0700 root root

    # create dalvik-cache and double-check the perms
    mkdir /data/dalvik-cache 0771 system system
    chown system system /data/dalvik-cache
    chmod 0771 /data/dalvik-cache

    # create the lost+found directories, so as to enforce our permissions
    mkdir /data/lost+found 0770
    mkdir /cache/lost+found 0770

    # double check the perms, in case lost+found already exists, and set owner
    chown root root /data/lost+found
    chmod 0770 /data/lost+found
    chown root root /cache/lost+found
    chmod 0770 /cache/lost+found
    # create LGDRM dirs if not exist
    mkdir /data/lgdrm 0770 lgdrm lgdrm_acc
    mkdir /data/lgdrm/cert 0770 lgdrm lgdrm_acc
    mkdir /data/wmdrm 0770 lgdrm lgdrm_acc
    mkdir /data/arcsoftDivx 0770 lgdrm lgdrm_acc
    chmod 0777 /dev/oncrpc/3000008e:fd348c74


   # create 3rd_party dir if not exist 
    mkdir /data/local/tmp/3rd_party 0777
    mkdir /data/local/tmp/3rd_party/ArcSoft 0777
    mkdir /data/local/tmp/3rd_party/ArcSoft/MediaGallery 0777
    mkdir /data/local/tmp/3rd_party/ArcSoft/MediaPlayer 0777
    mkdir /data/local/tmp/3rd_party/ArcSoft/Camera 0777

# LGE_CHANGE_S, [jinwoonam@lge.com] 2009-08-05, <Add debugfs for test & test app>
    mkdir /data/debug 0777 system system
    mount debugfs mtd@debugfs /data/debug
# LGE_CHANGE_E, [jinwoonam@lge.com] 2009-08-05, <Add debugfs for test & test app>

on boot
# basic network init
    ifup lo
    hostname localhost
    domainname localdomain

# set RLIMIT_NICE to allow priorities from 19 to -20
    setrlimit 13 40 40

# Set timeout value for rmnet stats.
    write /sys/devices/virtual/net/rmnet0/timeout_suspend 5000000

# Define the oom_adj values for the classes of processes that can be
# killed by the kernel.  These are used in ActivityManagerService.
    setprop ro.FOREGROUND_APP_ADJ 0
    setprop ro.VISIBLE_APP_ADJ 1
    setprop ro.SECONDARY_SERVER_ADJ 2
    setprop ro.HOME_APP_ADJ 4
    setprop ro.HIDDEN_APP_MIN_ADJ 7
    setprop ro.CONTENT_PROVIDER_ADJ 14
    setprop ro.EMPTY_APP_ADJ 15

# Define the memory thresholds at which the above process classes will
# be killed.  These numbers are in pages (4k).
    setprop ro.FOREGROUND_APP_MEM 1536
    setprop ro.VISIBLE_APP_MEM 2048
    setprop ro.SECONDARY_SERVER_MEM 4096
    setprop ro.HOME_APP_MEM 4096
    setprop ro.HIDDEN_APP_MEM 5120
    setprop ro.CONTENT_PROVIDER_MEM 5632
    setprop ro.EMPTY_APP_MEM 6144

    setprop ro.com.google.location_feature 1
# Write value must be consistent with the above properties.
# Note that the driver only supports 6 slots, so we have HOME_APP at the
# same memory level as services.
    write /sys/module/lowmemorykiller/parameters/adj 0,1,2,7,14,15

    write /proc/sys/vm/overcommit_memory 1
    write /proc/sys/vm/min_free_order_shift 4
    write /sys/module/lowmemorykiller/parameters/minfree 1536,2048,4096,5120,5632,6144

    # Set init its forked children's oom_adj.
    write /proc/1/oom_adj -16

    # Permissions for System Server and daemons.
    chown radio system /sys/android_power/state
    chown radio system /sys/android_power/request_state
    chown radio system /sys/android_power/acquire_full_wake_lock
    chown radio system /sys/android_power/acquire_partial_wake_lock
    chown radio system /sys/android_power/release_wake_lock
    chown radio system /sys/power/state
    chown radio system /sys/power/wake_lock
    chown radio system /sys/power/wake_unlock
    chmod 0660 /sys/power/state
    chmod 0660 /sys/power/wake_lock
    chmod 0660 /sys/power/wake_unlock
    # princlee@lge.com add permission to handle in Application 2009.08.26
    chown system system /sys/devices/platform/i2c-gpio.6/i2c-adapter/i2c-6/6-0044/enable
    chmod 0666 /sys/devices/platform/i2c-gpio.6/i2c-adapter/i2c-6/6-0044/enable
    chown system system /sys/class/timed_output/vibrator/enable
    chown system system /sys/class/leds/keyboard-backlight/brightness
    chown system system /sys/class/leds/lcd-backlight/brightness
    chown system system /sys/class/leds/button-backlight/brightness
    chown system system /sys/class/leds/jogball-backlight/brightness
    chown system system /sys/class/leds/red/brightness
    chown system system /sys/class/leds/green/brightness
    chown system system /sys/class/leds/blue/brightness
    chown system system /sys/class/leds/red/device/grpfreq
    chown system system /sys/class/leds/red/device/grppwm
    chown system system /sys/class/leds/red/device/blink
    chown system system /sys/class/leds/red/brightness
    chown system system /sys/class/leds/green/brightness
    chown system system /sys/class/leds/blue/brightness
    chown system system /sys/class/leds/red/device/grpfreq
    chown system system /sys/class/leds/red/device/grppwm
    chown system system /sys/class/leds/red/device/blink
    chown system system /sys/class/timed_output/vibrator/enable
    chown system system /sys/module/sco/parameters/disable_esco
    chown system system /sys/kernel/ipv4/tcp_wmem_min
    chown system system /sys/kernel/ipv4/tcp_wmem_def
    chown system system /sys/kernel/ipv4/tcp_wmem_max
    chown system system /sys/kernel/ipv4/tcp_rmem_min
    chown system system /sys/kernel/ipv4/tcp_rmem_def
    chown system system /sys/kernel/ipv4/tcp_rmem_max
    chown root radio /proc/cmdline
    chown bluetooth bluetooth /sys/module/bluetooth_power/parameters/power
    chown bluetooth bluetooth /proc/bluetooth/sleep/proto
    chown system system /sys/module/sco/parameters/disable_esco
    chmod 0660 /sys/module/bluetooth_power/parameters/power
    chmod 0660 /proc/bluetooth/sleep/proto
    chown bluetooth bluetooth /dev/ttyHS0
    chmod 0660 /dev/ttyHS0
    chmod 0666 /dev/msm_snd
    chown system system /dev/akm8973_daemon
    chown system system /dev/akm8973_aot
    chmod 0666 /dev/akm8973_daemon
    chmod 0666 /dev/akm8973_aot
#add by kimeh@lge.com
	chown radio system /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq
    chmod 0660 /sys/devices/system/cpu/cpu0/cpufreq/scaling_max_freq

# Define TCP buffer sizes for various networks
#   ReadMin, ReadInitial, ReadMax, WriteMin, WriteInitial, WriteMax,
    setprop net.tcp.buffersize.default 4096,87380,110208,4096,16384,110208
    setprop net.tcp.buffersize.wifi    4095,87380,110208,4096,16384,110208
    setprop net.tcp.buffersize.umts    4094,87380,110208,4096,16384,110208
    setprop net.tcp.buffersize.edge    4093,26280,35040,4096,16384,35040
    setprop net.tcp.buffersize.gprs    4092,8760,11680,4096,8760,11680

    class_start default

## Daemon processes to be run by init.
##
service console /system/bin/sh
    console

# adbd is controlled by the persist.service.adb.enable system property
service adbd /sbin/adbd
    disabled

# adbd on at boot in emulator
#on property:ro.kernel.qemu=1
#    start adbd

on property:persist.service.adb.enable=1
    start adbd

on property:persist.service.adb.enable=0
    stop adbd

#ln -s /dev/oncrpc/30000002:00010000 /dev/oncrpc/30000002:00010001

service servicemanager /system/bin/servicemanager
    user system
    critical
    onrestart restart zygote
    onrestart restart media

service vold /system/bin/vold
    socket vold stream 0660 root mount

service debuggerd /system/bin/debuggerd

service ril-daemon /system/bin/rild
    socket rild stream 660 root radio
    socket rild-debug stream 660 radio system
    user root
    group radio cache inet misc

service akmd2 /system/bin/akmd2
    
service zygote /system/bin/app_process -Xzygote /system/bin --zygote --start-system-server
    socket zygote stream 666
    onrestart write /sys/android_power/request_state wake
    onrestart write /sys/power/state on

service media /system/bin/mediaserver
    user media
    group system audio camera graphics inet net_bt net_bt_admin lgdrm_acc

service bootsound /system/bin/playmp3
    user media
    group audio
    oneshot

service dbus /system/bin/dbus-daemon --system --nofork
    socket dbus stream 660 bluetooth bluetooth
    user bluetooth
    group bluetooth net_bt_admin

# BTLA modification adding start on 20090602
# Make sure we startup btld before hcid
service btld /system/bin/logwrapper /system/bin/btld -hb 4000000 
    user root
    group bluetooth net_bt_admin
    disabled
    oneshot

# Start DTUN HCID
service hcid /system/bin/logwrapper /system/bin/hcid
    socket bluetooth stream 660 bluetooth bluetooth
    socket dbus_bluetooth stream 660 bluetooth bluetooth
    # init.rc does not yet support applying capabilities, so run as root and
    # let hcid drop uid to bluetooth with the right linux capabilities
    group bluetooth net_bt_admin misc
    disabled
    oneshot
# BTLA modification adding end on 20090602

#### original block start-comment out for BTLA ,not BlueZ on 20090602
#service hcid /system/bin/hcid -s -n -f /etc/bluez/hcid.conf
#    socket bluetooth stream 660 bluetooth bluetooth
#    socket dbus_bluetooth stream 660 bluetooth bluetooth
#    # init.rc does not yet support applying capabilities, so run as root and
#    # let hcid drop uid to bluetooth with the right linux capabilities
#    group bluetooth net_bt_admin misc
#    disabled
#### original block end-comment out for BTLA ,not BlueZ

service hfag /system/bin/sdptool add --channel=10 HFAG
    user bluetooth
    group bluetooth net_bt_admin
    disabled
    oneshot

service hsag /system/bin/sdptool add --channel=11 HSAG
    user bluetooth
    group bluetooth net_bt_admin
    disabled
    oneshot

service installd /system/bin/installd
    socket installd stream 600 system system

# Added by Sinverse to reduce factory reset time. 20090820.
service lgesystemd /system/bin/lgesystemd
    socket lgesystemd stream 600 system system

service flash_recovery /system/bin/flash_image recovery /system/recovery.img
    oneshot

busybox --install