Images of signatures being treated as an attachment

[elisio]

I am having a rather serious problem, when the person will reply or forward a message that needs to keep the original attachment, all the images of the previous signatures appear in the attachment field, all the images are treated as a specific attachment in some messages, As the exchange of emails is very intense, comes to have 80 to 100 images that are not actually attached but rather signature images.
This occurs even if the person who has the zimbra has no signature.
Is there any way to disable this behavior?
Thank you very much in advance.