Thank you for your help.
Next time I will RTFM.
I hope I will get much less false positive now.
Here is the list I made :
KS_BL_IGNORE=multipart,FONT,nbsp,name,boundary,Content-Type,NextPart,000,alternative,bgColor,—-,color,mixed,message,align,Arial,href,FONT-SIZE,face,FONT-FAMILY,border,class,COLOR,Microsoft,This,sans-serif,000080,www,application,cellSpacing,width,asp,
Regards,
Ben.