I have the wusb54gc_v1 which uses the rt73.sys driver and included it in the actual Ralink driver from Ralink. It is driver version 1.3.2.0 for Windows XP and 2k and available from Ralink website as of 11/11/2008. It has the DeviceID USB\VID_13B1&PID_0020. I was able to use ISCab and update all the *.inf and *.ini files to include the WUSB54GC_v1.

Let me answer "Fine, but..."
... modifying the *.inf file invalidates the digital signature. Ralink Tech. is going generic with some of their drivers. I think thats the right way to go. So the rt73.sys version 10/21/2008, 1.03.02.0000 now supports devices of 25 OEM manufacturers:

...
[Manufacturer]
%Ralink%        = Ralink
%Qcom%          = Qcom
%Gigabyte%      = Gigabyte
%Conceptronic%  = Conceptronic
%Surecom%       = Surecom
%Asus%          = ASUS
%Amit%          = AMIT
%CNet%          = CNet
%Huawei-3Com%   = Huawei-3Com
%Askey%         = Askey
%HP%            = HP
%Buffalo%       = Buffalo
%ZyXEL%         = ZyXEL
%Sitecom%       = Sitecom
%Netopia%       = Netopia
%Philips%       = Philips
%Zcom%          = Zcom
%AboCom%        = AboCom
%EnGenius%      = EnGenius
%Edimax%        = Edimax
%AL%            = AL
%Planex%        = Planex
%Samsung%       = Samsung
%Billionton%    = Billionton
%D-Link%        = D-Link
...

This support requirers some cooperation between the chipset vendor (Ralink) and the OEM vendors. As you can see LinkSys is not on the list. Whoever is responsible for that, I do not intend to make his work.
So I included in the last Beta Driverpack WLAN this Ralink driver and the WUSB54GCv1 driver, version 01/12/2006, 1.00.04.0000, that also has a digital signature.
Mwvonlehe, I'll send you an email with the link zu this Beta driverpack. Please test and report back if it works for you.

I will have a look on this soon.

We never use drivers from E-mail or Rapidshare or other... thanks for offering.

OEM or Manufacturer sources / links only.

I also have the Linksys WMP54G_v4.1 which uses the rt61.sys driver for XP and 2k and included it in the actual Ralink driver from Ralink. It is driver version 1.2.6.0 and has the device ID of PCI\VEN_1814&DEV_0301&SUBSYS_00551737. It was available to download from Ralink on 12/9/2008. I have tested it on Windows XP 32 bit but should work on all platforms.

I also included instructions on how to update the original driver to include the above Linksys hardware.

I'm also interested in seeing the WUSB54GC added. Here is my HWID result.

===========
USB Devices
===========
...
USB\VID_13B1&PID_0020\5&27FF6FC&0&1                         : Compact Wireless-G USB Adapter #2
...

ehp,
found the driver on LinkSys's website, I'm going to integrate it in the next beta DP_WLAN and inform you when it will be available. BTW: Your model it is WUSB54GCv1

===========
PCI Devices
===========
PCI\VEN_10EC&DEV_8139&SUBSYS_805B1043&REV_10\4&24AB0D93&0&68F0: Realtek RTL8139/810x Family Fast Ethernet NIC
PCI\VEN_11C1&DEV_044E&SUBSYS_044E1235&REV_02\4&24AB0D93&0&50F0: Lucent Win Modem
PCI\VEN_1282&DEV_9102&SUBSYS_50323030&REV_31\4&24AB0D93&0&40F0:  CNet PRO200 PCI Fast Ethernet Adapter           
PCI\VEN_8086&DEV_2410&SUBSYS_00000000&REV_02\3&61AAA01&0&F8 : Intel(r) 82801AA LPC Interface Controller
PCI\VEN_8086&DEV_2411&SUBSYS_24118086&REV_02\3&61AAA01&0&F9 : Intel(r) 82801AA Bus Master IDE Controller
PCI\VEN_8086&DEV_2412&SUBSYS_24128086&REV_02\3&61AAA01&0&FA : Intel(r) 82801AA USB Universal Host Controller
PCI\VEN_8086&DEV_2415&SUBSYS_806A1043&REV_02\3&61AAA01&0&FD : SoundMAX Integrated Digital Audio
PCI\VEN_8086&DEV_2418&SUBSYS_00000000&REV_02\3&61AAA01&0&F0 : Intel(r) 82801AA PCI Bridge
PCI\VEN_8086&DEV_7124&SUBSYS_00000000&REV_03\3&61AAA01&0&00 : Intel(r) 82810e DC-133 System and Graphics Controller
PCI\VEN_8086&DEV_7125&SUBSYS_801E1043&REV_03\3&61AAA01&0&08 : Intel(R) 82810E Graphics Controller
10 matching device(s) found.

===========
USB Devices
===========
USB\ROOT_HUB\4&12F0DD96&0                                   : USB Root Hub
USB\VID_0424&PID_0140\5&27FF6FC&0&2                         : Generic USB Hub
USB\VID_13B1&PID_0020\5&27FF6FC&0&1                         : Compact Wireless-G USB Adapter #2
3 matching device(s) found.

=============
Input Devices
=============
No matching devices found.

============
ACPI Devices
============
ACPI\FIXEDBUTTON\2&DABA3FF&0                                : ACPI Fixed Feature Button
ACPI\PNP0000\4&264480D3&0                                   : Programmable interrupt controller
ACPI\PNP0100\4&264480D3&0                                   : System timer
ACPI\PNP0200\4&264480D3&0                                   : Direct memory access controller
ACPI\PNP0303\4&264480D3&0                                   : HP PS2 Keyboard (2K - 3)
ACPI\PNP0401\4&264480D3&0                                   : ECP Printer Port (LPT1)
ACPI\PNP0501\1                                              : Communications Port (COM1)
ACPI\PNP0501\2                                              : Communications Port (COM2)
ACPI\PNP0700\4&264480D3&0                                   : Standard floppy disk controller
ACPI\PNP0800\4&264480D3&0                                   : System speaker
ACPI\PNP0A03\2&DABA3FF&0                                    : PCI bus
ACPI\PNP0B00\4&264480D3&0                                   : System CMOS/real time clock
ACPI\PNP0C01\2&DABA3FF&0                                    : System board
ACPI\PNP0C02\1                                              : Motherboard resources
ACPI\PNP0C02\2                                              : Motherboard resources
ACPI\PNP0C04\4&264480D3&0                                   : Numeric data processor
ACPI\PNP0C0C\2&DABA3FF&0                                    : ACPI Power Button
ACPI\PNP0F13\4&264480D3&0                                   : PS/2 Compatible Mouse
ACPI\PNPB006\4&264480D3&0                                   : MPU-401 Compatible MIDI Device
ACPI\PNPB02F\4&264480D3&0                                   : Standard Game Port
ACPI_HAL\PNP0C08\0                                          : Microsoft ACPI-Compliant System
ROOT\ACPI_HAL\0000                                          : ACPI Uniprocessor PC
22 matching device(s) found.

============
HDA Audio
============
No matching devices found.

============
RAID Devices
============
PCI\VEN_8086&DEV_2411&SUBSYS_24118086&REV_02\3&61AAA01&0&F9
    Name: Intel(r) 82801AA Bus Master IDE Controller
    Hardware ID's:
        PCI\VEN_8086&DEV_2411&SUBSYS_24118086&REV_02
        PCI\VEN_8086&DEV_2411&SUBSYS_24118086
        PCI\VEN_8086&DEV_2411&CC_010180
        PCI\VEN_8086&DEV_2411&CC_0101
    Compatible ID's:
        PCI\VEN_8086&DEV_2411&REV_02
        PCI\VEN_8086&DEV_2411
        PCI\VEN_8086&CC_010180
        PCI\VEN_8086&CC_0101
        PCI\VEN_8086
        PCI\CC_010180
        PCI\CC_0101
1 matching device(s) found.

your link

is no longer valid. I'm working on driverpacks WLAN and would like to process your request to support your stick in further versions. To do this I need the hardare ID of your modell. There are 3 versions of WUSB54GC wich seems to have completely diffrent controller chips inside. If you are still interested that Driverpacks WLAN supports your modell in a future release, please use HWID's tool and post the results here.