Steps to reproduce:

1. Compile for Android and run aTestApp included in sources.
2. Generate QR-code for 12 string (I've used online QR-code generator).
3. Try to scan this code with the test application. Application does not recognize this QR-code.

If to prepend/insert/append any alpha-character to a QR-code, it is recognized then.
Tested for "a1", "1a2" or "1a"

Patch is ready and will be PR-ed in minutes.

Also, see issue #11 (QR-code of one-digit numeric string is not recognized)