Modify your WPCF7 Mails with conditions.
Note: Complex if statements are not yet supported. Please contact me if you need this.
Before the WP Contact Form 7 Plugin sents a mail this plugin becomes active. It looks for if-conditions written in shortcode-style and evaluates if the condition variable is empty or not. Depending on that the block between [if] and [/if] is inserted into the mail or not.
[if phone]Phone number: [phone][/if]