I noticed that myself. However, the preceding sentence
does call out gender identity.
Here's the letter I sent them:
QuoteApril 21, 2010
Dear Representative Ryan,
Dear Senator Feingold,
Dear Senator Kohl,
I am writing to you to urge you to support the passage of the Employment Non-Discrimination Act (ENDA). This bill would add sexual orientation and gender identity to existing federal employment non-discrimination laws.
Because transgender people are not currently protected by federal legislation and because of widespread discrimination against the community, transgender people face significant levels of unemployment due to prejudices in hiring and retention of transgender workers. The loss of a job due to discrimination leads to economic hardship and instability.
I believe that we should be evaluated for the work that we do and our ability to do our jobs. Federal anti-discrimination legislation sends an important message to employers that intolerance in the workplace is unacceptable in the United States. I hope that you will join me in supporting ENDA.
Sincerely,
Me
Post Merge: April 28, 2010, 12:10:06 PM
The response from Senator Kohl. Also supports our cause!!

Quote
Thank you for contacting me about the Employment Non-Discrimination Act (ENDA). I appreciate hearing from you and welcome the opportunity to respond.
As you may know, Representative Barney Frank (D-MA) introduced H.R. 3017, the Employment Non-Discrimination Act, on June 24, 2009. This legislation would extend civil rights protections to prohibit workplace discrimination based on sexual orientation. Senator Jeff Merkley (D-OR) introduced the Senate companion bill, S. 1584 on August 5, 2009. S. 1584 was referred to the Senate Health, Education, Labor and Pensions Committee. Although I am not a member of this committee, I will keep your views in mind should this legislation come before the full Senate.
I believe that fair and equal treatment of all Americans is the cornerstone of our society and our political system. Despite great progress, the struggle for civil rights and equal treatment under the law continues today for many citizens. I am committed to ending discrimination in our society.
Again, thank you for contacting me.
Sincerely,
Herb Kohl
United States Senator