Can't get metaWeblog.newPost to work

I cannot get a newpost to work... I copied your example xml word for word replace my username, secret word, post title, description, and a good catagory. I get Invalid Blog Content Parameter as a fault.

I can get catagories so I know my username and password are good. Below is the xml I pass:

<methodCall>

<methodName>metaWeblog.newPost</methodName>

<params>

<param><value><string>MyBlog</string></value></param>

<param><value>goodusername</value></param>

<param><value><string>goodsecretword</string></value></param>

<param><struct>

<member><name>categories</name>

<value><array><data><value>key1</value></data></array></value></member>

<member><name>description</name><value>hello world</value></member>

<member><name>title</name><value>hello world</value></member>

<member><name>dateCreated</name><value><dateTime.iso8601>20060518T09:00:24</dateTime.iso8601></value></member>

</struct></param>

<param>1</param>

</params></methodCall>

[1454 byte] By [RobSmith] at [2008-2-19]