I believe you're talking about where it says, "Login to the account failed, please try again." I ran into the exact same issue on two out of my three Exchange accounts. Took me FOREVER to figure out how to correct it.
I can't personally verify these these instructions, but from what I was reading, you setup your Gmail as a Corporate Sync account. Then, once you've done that, you go back into the settings of that account and type in your actual Exchange account settings:
Corporate Sync -- Cannot connect to server
What I ended up doing to get mine to work was very similar, though--seeing as how I was able to get one of my Exchange accounts to work, I set that one up and just changed the settings to match my other Exchange account.
This issue could all be remedied if they'd give you the option to manually setup the account settings...hopefully, it will be fixed in the next update.