Bugs in Mono Implementation of XmlSchema:

1.
None of the XmlSchemaObjects except the XmlSchema populate XmlSerializerNamespaces.

2.
Non schema attributes are not being handled. Need an internal XmlAttribute constructor.
3.
Documentation and appInfo's Markup is not being read in the Read() Method.

4.
Handling of unique particle attribution of sequences is almost complete, 
but not perfect. Note that it is W3C specification that is so buggy. 
Basically there is neither formalization nor even normative definition 
about unique particle attribution. Appendix H tried to describe about 
that, but it is too incomplete.

5.
Currently ContentTypeParticle does not eliminate "pointless" (see 3.9.6 of
xml schema structures spec) XmlSchemaChoice, like MS.NET. It causes
incorrect DBR validation.

6.
See MS-BUGS.txt 008 and 014. There are some correction and we should fix our
implementation based on those wrong premises.