What steps will reproduce the problem?
1. http://tip.golang.org/pkg/encoding/xml/#Marshal

What is the expected output?

- a field with tag ",attr" becomes an attribute with the
  field name in the XML element.

What do you see instead?

- a field with tag ",attr" becomes an attribute with the
  field name in the in the XML element.

Which compiler are you using (5g, 6g, 8g, gccgo)?

N/A

Which operating system are you using?

N/A

Which version are you using?  (run 'go version')

tip and 1.0.3

Please provide any additional information below.