conditional in conditional

Hi,
i´m using some code like this in my thank you page.
If the user checked Newsletter, this code will be loadet in the thank you page:

[gravityforms action="conditional" merge_tag="{newsletter.:13.1}" condition="greater_than" value="1"]<iframe src="http://url.com/?gender=HERE-IS-MY-PROBLEM&email={E-Mail:6}" width="1" height="1" frameborder="0"></iframe>
[/gravityforms]

Works fine... But i have troubles with the gender value.

In my form is a dropdown with "male/female". But i need in my url a 0 for male and a 1 for female. So i have tryed to put a conditional shortcode in another. That causes errors.

Have you any ideas for me?
Something like:
IF GENDER == MALE ->0 ELSE 1

Thank you

Sorry, i think i don´t understand ;-)

The problem is that i have put a shortcode in a shortcode...

Example: This won´t work

[gravityforms action="conditional" merge_tag="{newsletter:5}" condition="is" value="1"]
some code

[gravityforms action="conditional" merge_tag="{gender:2}" condition="is" value="1"]
some code
[/gravityforms]
[/gravityforms]

Is it possible to use PHP on the thank you message? Than i coult build a little switch...