Strange plugin translation problem

Hi,
I have gravity forms in conjunction with wpml's gravity forms multilingual and I can translate the form I have created fine, but I have a problem with the plugin translation.
I have two languages in wpml, catalan and spanish, being catalan the default one. The problem I have is that I have created a (very basic) catalan .mo, but (with the web in catalan) the form errors (required fields for instance) are shown in spanish. Locale is "ca" and works fine with wp or nextgen gallery, but even, I tried different .mo names or tried using a valid .mo (finnish one specifically) to see if the problem was my .mo file. But the form error messages still appear in spanish.
Another strange thing is that in admin everything is shown in catalan (wordpress, nextgen gallery, ...), but gravity forms is shown in spanish! Should not default to english if catalan translation is not present? I also tried changing some admin strings in the catalan translation, but everything was still shown in spanish.
Any help would be appreciated!
Thanks in advance
Pau

wp-config is set to spanish, but other plugins get the locale from WPML, that is why is "strange". With this information you gave me I did some more searching and I found this page that explains why some plugins got the WPML language while gravity forms don't. I changed the gravity forms code and now it works as I expected.

To summarize the content on the page:

Moving the call to load_plugin_textdomain() to the init action gave WPML time to set the locale first:

add_action( 'init', 'plugin_init' );

function plugin_init() {
  // localization in the init action for WPML support
  load_plugin_textdomain( 'my_textdomain', false, dirname( plugin_basename( __FILE__ ) ) . '/languages' );
}

I have changed the code in my install, but that will break the updates, can you evaluate changing your code to make the plugin fully WPML compatible? I don't know if it breaks anything (in my quick test didn't find anything wrong), but it will be a plus, besides, WPML lists gravity forms as a multilingual form plugin, so it will play nice.
Thanks for your help
Pau

Thanks Pau, your suggestion solved the same problem I faced with an Italian-German WP installation.
Wainting for a plugin update to solves the problem officially.
Saverio