Better_Boy's very first link (above) 404s.
If anyone needs it, it is
Post 93 of this thread
This solution should be better as you can theoretically use any microsd card, not just one with a hackable CID.
USB Image Tool - for creating image of original microsd
If you can't backup your own microsd image, try this
IMAGE
To read the CID of the microsd card from an Android phone that isn't rooted, you could try
THIS
Attached the necessary progs.7z (now progs.zip to be forum compliant) - for preparing the new microsd