After open a couple of mp3 in a text editor I found that most of the mp3 that displays in the lame tag crc:corrupt contain at the end a line similar to this:

LYRICSBEGININD0000200CRC00008D2102C18000037LYRICS200

I test those mp3 with mp3test and this program report these bytes as junk, so I tried deleting this line (some kind of lyric tag?) and then I check again the file with encspot and guess what? now the lame tag displays crc:ok
I consulted for this to the mp3trim author and he say that the lame tag and this kind of lyric tag are unrelated. I supose that the corrupt crc in lame tag is due to the addition of the lyric tag after the encoding process and the solutions would be update the crc in lame tag to include the lyric tag in that check or delete the lyric tag.
So I would like to know if this lyric tag is really extra-info and if it can be removed in batch mode with some program.

Thanks in advance for any help

This is an error in the program you are using to check Lame tags.
The Lame music crc is the crc of the music part of your file (ie without extra tags such as the Lame header itself).
I guess the program you are using is assuming that everything after the vbr header is supposed to be music. However, this lyrics3 tag, beeing located AFTER music should not be included when computing the music crc.

I understand now, thanks for your reply Gabriel