Well, after having bought a couple of WIFI dongles that don't work, I finally find the right one.
It is the:

Brand: EDIMAX, Model: EW-7318Ug, FCC ID: NDD9573180610, MPN: EW7318UG85CC12956

Cheers.

The WiFi dongleBy penbex

It gets fairly warm! Also, reception does not seem to be as good as my other wireless devices. So lets take a closer look. On the front of the WiFi stick There is a big G and on the back a label with the FCC ID NDD 9573180610. Using that number and the FCC website you can obtain the FCC Test documents which provide detailed information.

Manufacturer’s company: EDIMAX TECHNOLOGY CO., LTD.

Product Name: 802.11g Turbo Wireless LAN USB Adapter

Model (Brand) Name EW-7318UG V3.0 (EDIMAX) / GWU-E18G (GLP)

We are dealing with an Edimax EW-7318UG. From the picture (taken from the FCC report) it is clear that it is using the RT2571 chipset. Also, The RomFS directory /etc/Wireless/Rt73sta seems to contain the driver. So, if the stick ever dies or you just want to try a different stick then one with the same chipset should work without problems.