rkaunas on "[Plugin: Contact Form 7] Function overriding"

Hi,

i like your plugin very much. Thank you for it.

I have a little problem - contact form is sending empty tags to email:

[cargo-desc-title][cargo-desc][cargo-volume-title][cargo-volume][cargo-weight-title][cargo-weight][cargo-kg]<br/>
 [cargo-desc-title_1][cargo-desc_1][cargo-volume-title_1][cargo-volume_1][cargo-weight-title_1][cargo-weight_1][cargo-kg_1]<br/>
 [cargo-desc-title_2][cargo-desc_2][cargo-volume-title_2][cargo-volume_2][cargo-weight-title_2][cargo-weight_2][cargo-kg_2]<br/>

I need tags to be send only if they are filled from inputs - else they are blank and not sending. I found that in contact-form-7/includes/classes.php is function mail_callback. If i commentout "return special" - everythink works as i want, but when update will come - it will collapse.

So, is it possible to overrite function, that is in class "WPCF7_ContactForm"? What solution would you suggest?

http://wordpress.org/extend/plugins/contact-form-7/