Newsletter going to spam folder or marked as phishing#

Just looking for some general help with Newsletters.
I have TXNewsletters set up and a good portion of the recipients dont seam to receive the newsletter.
A few have mentioned it going to spam and one getting a phishing warning.

Has anyone had the same problem?
Any tricks or tips?

Some info here: http://www.google.com/support/forum/p/gmail/thread?tid=155badfb3131ef5d&hl=en

And here: http://www.aweber.com/faq/questions/265/__fav

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PLEASE, PLEASE specify the version of MODX you are using . . . PLEASE!
MODx info for everyone: http://bobsguides.com/modx.html

Thanks Bob!

I tried these already plus some others. They all come back around 95% approved.
I guess it comes down to the hosting server.

This happens to many people, that's why sometimes it is better to manage them with mailchimp or ymlp.

The newsletter goes to spam for many reasons, for example:
1. (IP) Server with bad reputation
2. The newsletter has attachments
3. Some words are blacklisted, I think they also recognize if the title is ALL IN CAPITAL LETTERS
4. Heavy template design (lot of images, linked to unreliable server).
5. Email of the sender different from the email of the website, for example, if the sender is: username@gmail.com and the website is sitename.com, I think that it would be better to have it sent from noreply@sitename.com

Thanks.

I did a heap of testing.
1. I doubt this is it in my case, but maybe
2. nope checked
3. nope checked
4. this could be it but I tested a blank page and same thing happened
5. nope checked

Anyway I guess mailchimp is the way to go.