I found a mistake in the class, the character A is wrong.
The error is here and the author has used this website to create his class:
barcodeisland.com/code39.phtml.
To fix it, just replace this in the function _c39Encode :
"A" => "NNWWNNWNN",
by:
"A" => "WNNNNWNNW",
romain - 2011-06-30 14:31:19
