XML-standard

Hi!
I'm performing a master project and it deals with choosing a standard for
XML-based message handling. 
As I know the most popular standards that are in use today are: ebXML, OAGI,
RosettaNet and Biztalk.

I'm wondering if anybody perhaps could help me to make right decision, i.e.
choose the right 
standard for the company's messaging system. Which aspects are most
important to take into considerations?

Thanks 

MVH/Brgds
Mozhgan Moussavi
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Mozhgan H. Moussavi
Student of "Master Degree on Software Engineering"
Blekinge Institute of Technology, SWEDEN
Mobile: +46-704-97 38 81
Home: +46-40-23 35 23
Email: 
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